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View Full Version : The "let's brainstorm how to make a piggyback work" thread


eTiMaGo
03-24-2009, 04:10 AM
OK guys, as most of you know, getting a piggyback to work on a USDM yaris has been a major PITA for those who have tried.

That being said, we seem to be (at least I am) a bit in the dark as to why and how that is.

So I propose we use this thread to discuss what has been tried, what hurdles have been met with, and how we could do this.

Let's remember the Yaris is not some magical device conjured out of the mind of a madman... It is a human construction based on human-devised electronic systems, and thus these systems can be reverse-engineered by other humans :biggrin:

I, unfortunately, have no experience in this outside of the theoretical, but I've been reading the technical/repair manuals in quite a lot of detail and have a good understanding of the various quirks of this car, especially with regards to its emissions systems... so let the discussion begin!

jinxor
03-24-2009, 05:41 AM
Sorry for being a n00b... but can you explain what a piggyback is as well at the beginning of the thread please

tk-421
03-24-2009, 06:05 AM
Sorry for being a n00b... but can you explain what a piggyback is as well at the beginning of the thread please
Google is your friend:
http://www.innovatemotorsports.com/resources/piggy-back.php
http://forums.superstreetonline.com/70/1010816/ecu-tuning-electronics/engine-tuning-standalone-ecu-vs-piggy-back-ecu-eng/index.html

Sabretooth
03-24-2009, 01:25 PM
Honestly, had you thought about getting a USDM unit Thomas and trying to take it to TRD Thailand? See what they can come up with, they seemed to help you in the past about trying to sort out what Engine swaps were viable in the past.

We dont have those kind of tuning places here in the states, or at least a mainstream company that can sit there and devote time and money to try and reverse engineer it for us.

yaris-me
03-24-2009, 02:01 PM
I think Toyota has engineered the car to be reliable and has built in a margin of safety for the engine. On the surface, the engine seems to have been designed for performance yet it is detuned by a margin of safety. So, I think the problem is in the ECU programming and not a piggyback. Finding a way to alter or change the programming is the way.:wink:

jkuchta
03-24-2009, 02:29 PM
Reading through the Engine management section of the factory manual, there seems to be a route to add/subtract fuel and spark with an intelligent tester plugged into the OBD-II port. There is a way to also turn off the DFCO and a bunch of other things.


Anyone have access to an intelligent tester?

dallas
03-25-2009, 01:15 AM
The problem is not the cars complex unbreakable programs, it's the lack of tuners and enthusiasts who are willing to figure this out, that leaves us newbies on the forums to figure it out on our own. Even the suppliers don't want to waste any money to offer a real turn key kit, they want us to figure it out and be their North American guinea pigs. That being said, NT Nooge, and several other guys that have the Blitz supercharger that are working hard to get the most out of this kit, and get the tuning dialed in. Sadly this is a Econo car not a Sports car.

Its funny I was just on a Genesis Coupe form and because its a 2.0 turbo, it's not much faster stock than a Yaris 0-60 in 8 seconds, Hyundai has done a great job to make it tuner friendly, they hooked up with companies like AEM and AMS to make stuff for the car, I bet in no time this platform will be over 300 hp. And at $22,000 a rear wheel drive with 200 hp, big Brembo brakes that looks like a G37 Nissan is very attrative right now.
I hope we can figure out a safe reliable way to get an honest 130 at the wheels of out the Yaris, the lack of Hp has my eyes wandering LOL

Nexus1155
03-25-2009, 01:22 AM
^^^ yeah but you have to take into account that the genesis weighs 3500lbs when the yaris weighs around 2000. Thats a 1500 lb difference, i think you would be as fast as the yaris is you weighed that much...

eTiMaGo
03-25-2009, 02:34 AM
Honestly, had you thought about getting a USDM unit Thomas and trying to take it to TRD Thailand? See what they can come up with, they seemed to help you in the past about trying to sort out what Engine swaps were viable in the past.

We dont have those kind of tuning places here in the states, or at least a mainstream company that can sit there and devote time and money to try and reverse engineer it for us.

That is definitely an option, can anyone get their hands on an ECU from a salvaged car? I checked some time ago with ROCKLAND TOYOTA, the part numbers are completely different between our ECUs here and the USDM ones.

i believe the major hurdle is the ECU, its just too well protected and is not add-on friendly. what would need to be done is a interface between the ECU and the piggyback, not to "fool" the ECU but merely reroute its responses.

One of the main problem, I think, which prevents simple piggybacks like the S-AFC which modify the MAF signal, is that the ECU uses data from the AF and O2 to check on the final air/fuel ratio, and override whatever data it is getting from the MAF (fuel trim function)

I think Toyota has engineered the car to be reliable and has built in a margin of safety for the engine. On the surface, the engine seems to have been designed for performance yet it is detuned by a margin of safety. So, I think the problem is in the ECU programming and not a piggyback. Finding a way to alter or change the programming is the way.:wink:

Yes, an ECU tweak is usually the fastest, cheapest and most warranty-friendly way to do this. But nobody yet seems to know how to do that, and it would require some pretty advanced electronics knowledge and experience, beyond the scope of this discussion.

Reading through the Engine management section of the factory manual, there seems to be a route to add/subtract fuel and spark with an intelligent tester plugged into the OBD-II port. There is a way to also turn off the DFCO and a bunch of other things.


Anyone have access to an intelligent tester?

I think that is only for diagnostic purposes, once you return the car to normal usage it will re-adjust itself.

I checked eBay for those intelligent testers, $2000+ :laugh:

The problem is not the cars complex unbreakable programs, it's the lack of tuners and enthusiasts who are willing to figure this out, that leaves us newbies on the forums to figure it out on our own. Even the suppliers don't want to waste any money to offer a real turn key kit, they want us to figure it out and be their North American guinea pigs. That being said, NT Nooge, and several other guys that have the Blitz supercharger that are working hard to get the most out of this kit, and get the tuning dialed in. Sadly this is a Econo car not a Sports car.


Sad but true, unfortunately. Same reason Holdener seems to have given up on the intake manifold, it'll never sell enough to be worth the trouble. But hey, we are owners and fans of the cars, we're (mostly) not stupid, we can figure this out together somehow!

Its funny I was just on a Genesis Coupe form and because its a 2.0 turbo, it's not much faster stock than a Yaris 0-60 in 8 seconds, Hyundai has done a great job to make it tuner friendly, they hooked up with companies like AEM and AMS to make stuff for the car, I bet in no time this platform will be over 300 hp. And at $22,000 a rear wheel drive with 200 hp, big Brembo brakes that looks like a G37 Nissan is very attrative right now.
I hope we can figure out a safe reliable way to get an honest 130 at the wheels of out the Yaris, the lack of Hp has my eyes wandering LOL

Yeah that Genesis coupe is gonna make some big waves in the future of import tuning in the US, beating Nissan and Toyota at their own game... But let's stay on topic :biggrin:

eTiMaGo
03-25-2009, 03:23 AM
Just gonna note down a few ideas here for reference...

Repair manual description of operation of the various sensors:

Mass Air Flow:

The MAF meter is a sensor that measures the amount of air flowing through the throttle valve. The ECM
uses this information to determine the fuel injection time and to provide an appropriate air-fuel ratio. Inside
the MAF meter, there is a heated platinum wire which is exposed to the flow of intake air. By applying a
specific electrical current to the wire, the ECM heats it to a specific temperature. The flow of incoming air
cools both the wire and an internal thermistor, affecting their resistance. To maintain a constant current
value, the ECM varies the voltage applied to these components of the MAF meter. The voltage level is
proportional to the airflow through the sensor, and the ECM uses it to calculate the intake air volume.
The ECM monitors the average engine load value ratio to check the MAF meter for malfunctions. The
average engine load value ratio is obtained by comparing the average engine load calculated from the
MAF meter output to the average engine load estimated from the driving conditions, such as the engine
speed and the throttle opening angle. If the average engine load value ratio is below the threshold value,
the ECM determines that the intake air volume is low, and if the average engine load value ratio is above
the threshold value, the ECM determines that the intake air volume is high.
If this is detected in 2 consecutive driving cycles, the MIL is illuminated and a DTC is set.

Intake Air Temperature sensor:

The Intake Air Temperature (IAT) sensor, mounted on the Mass Air Flow (MAF) meter, monitors the IAT.
The IAT sensor has a built in thermistor with a resistance that varies according to the temperature of the
intake air. When the IAT is low, the resistance of the thermistor increases. When the temperature is high,
the resistance drops. These variations in resistance are transmitted to the ECM as voltage changes (see
Fig. 1).
The IAT sensor is powered by a 5 V supply from the THA terminal of the ECM, via resistor R.
Resistor R and the IAT sensor are connected in series. When the resistance value of the IAT sensor
changes, according to changes in the IAT, the voltage at terminal THA also varies. Based on this signal,
the ECM increases the fuel injection volume when the engine is cold to improve driveability.


(Both MAF and IAT sensors are located in the plastic "plug" that goes into your intake)

Front A/F sensor:

The A/F sensor generates a voltage* that corresponds to the actual air-fuel ratio. This sensor voltage is
used to provide the ECM with feedback so that it can control the air-fuel ratio. The ECM determines the
deviation from the stoichiometric air-fuel ratio level, and regulates the fuel injection time. If the A/F sensor
malfunctions, the ECM is unable to control the air-fuel ratio accurately.
The A/F sensor is of the planar type and is integrated with the heater, which heats the solid electrolyte
(zirconia element). This heater is controlled by the ECM. When the intake air volume is low (the exhaust
gas temperature is low), a current flows into the heater to heat the sensor, in order to facilitate accurate
air-fuel ratio detection. In addition, the sensor and heater portions are narrower than the conventional
type. The heat generated by the heater is conducted to the solid electrolyte through the alumina, therefore
the sensor activation is accelerated.
In order to obtain a high purification rate of the carbon monoxide (CO), hydrocarbon (HC) and nitrogen
oxide (NOx) components in the exhaust gas, a TWC is used. For the most efficient use of the TWC, the
air-fuel ratio must be precisely controlled so that it is always close to the stoichiometric level.


Rear O2 Sensor:

In order to obtain a high purification rate of the carbon monoxide (CO), hydrocarbon (HC) and nitrogen
oxide (NOx) components in the exhaust gas, a TWC is used. For the most efficient use of the TWC, the
air-fuel ratio must be precisely controlled so that it is always close to the stoichiometric air-fuel level. For
the purpose of helping the ECM to deliver accurate air-fuel ratio control, a Heated Oxygen (HO2) sensor
is used.
The HO2 sensor is located behind the TWC, and detects the oxygen concentration in the exhaust gas.
Since the sensor is integrated with the heater that heats the sensing portion, it is possible to detect the
oxygen concentration even when the intake air volume is low (the exhaust gas temperature is low).
When the air-fuel ratio becomes lean, the oxygen concentration in the exhaust gas is rich. The HO2
sensor informs the ECM that the post-TWC air-fuel ratio is lean (low voltage, i.e. less than 0.45 V).
Conversely, when the air-fuel ratio is richer than the stoichiometric air-fuel level, the oxygen concentration
in the exhaust gas becomes lean. The HO2 sensor informs the ECM that the post-TWC air-fuel ratio is
rich (high voltage, i.e. more than 0.45 V). The HO2 sensor has the property of changing its output voltage
drastically when the air-fuel ratio is close to the stoichiometric level.
The ECM uses the supplementary information from the HO2 sensor to determine whether the air-fuel ratio
after the TWC is rich or lean, and adjusts the fuel injection time accordingly. Thus, if the HO2 sensor is
working improperly due to internal malfunctions, the ECM is unable to compensate for deviations in the
primary air-fuel ratio control.


Information on the Active AF Ratio control (ECU's automatic check of catalytic converter function by forcing rich/lean/rich/lean ratios and verifying O2 sensor output):
http:/www.etimago.com/yaris/repairmanual/Engine%20Control.pdf - page 126 onward, and page 187 onward

About the short term and long term fuel trims:

The fuel trim is related to the feedback compensation value, not to the basic injection time. The fuel trim
consists of both the short-term and the long-term fuel trims.
The short-term fuel trim is fuel compensation that is used to constantly maintain the air-fuel ratio at
stoichiometric levels. The signal from the Air-Fuel Ratio (A/F) sensor indicates whether the air-fuel ratio is
rich or lean compared to the stoichiometric ratio. This triggers a reduction in the fuel injection volume if the
air-fuel ratio is rich and an increase in the fuel injection volume if it is lean.
Factors such as individual engine differences, wear over time and changes in operating environment
cause short-term fuel trim to vary from the central value. The long-term fuel trim, which controls overall
fuel compensation, compensates for long-term deviations in the fuel trim from the central value caused by
the short-term fuel trim compensation.
If both the short-term and long-term fuel trims are lean or rich beyond predetermined values, it is
interpreted as a malfunction, and the ECM illuminates the MIL and sets a DTC.
When the total of the short-term and long-term fuel trim values is within 20 % (and the engine coolant
temperature is more than 75°C [167°F]), the system is functioning normally.


It's a lot to take in, but these are the basic components that makes the ECU too smart for our own good :biggrin:

It would stand to reason, thus, that successfully running a piggyback would require tweaking the signals not only from the MAF/IAT, but also from the A/F and O2 sensor, so that they report values within the nominal range no matter what. Anybody know of a piggyback that can actually do that? I think the Greddy e-manage Ultimate has some user-programmable inputs and outputs, this could be a contender.

There are O2 sensor simulators in the market that have this sort of functionality, but I do not think they can handle the AF active control check?

Further things to look into:
*How the Blitz fuel controller hooks up, what signals does it affect. This seems to be the only working solution at the moment, in theory anyway.
Can someone email me the installation instructions PDF?

*Compare the functionality of various piggybacks available on the market.

eTiMaGo
03-25-2009, 10:10 AM
hey that's a great idea!

Loren
03-25-2009, 10:41 AM
What if you went and got sneaky:

The whole system is trying to maintain the AFR at stoich (or probably even leaner in cruise). It gets that info from the O2 sensor(s).

A person who understood how those sensors work could build a circuit to modify their output so that instead of giving the stoich reading at 14.7, it gave a stoich reading at 13.5 or 13.0 or 12.5. The ECU will see 14.7 in that condition and be happy.

A person who's not quite so savvy, but has a little money could just get a commonly available wideband O2 sensor kit, such as the Innovate LC-1, which has programmable outputs. You can have it output whatever voltage range you want, so you could tweak it to lie to the ECU in whatever way you want.

Something to consider, anyhow. Seems like an easy way to get the car to run richer across the board. It won't retard the timing for you, but it will address fueling.

ChinoCharles
03-25-2009, 10:50 AM
http://perfectpower.com/products/smt8.asp

AFAIK they should have the pinout for the Yaris on file. Nobody has contacted them yet?

eTiMaGo
03-25-2009, 10:50 AM
sounds like that could work too, but what really worries me is the self-test check the ECU does (very rich for a second, then very lean, and see how the sensor reacts. If it does not react, CEL)

though looking back at the manual's explanation, The HO2
sensor informs the ECM that the post-TWC air-fuel ratio is lean (low voltage, i.e. less than 0.45 V). That sounds like reducing the voltage of the sensor's output should be enough to trick the ECU into thinking the system is lean, thus enriching the mixture? Problem is, no way to tune that...

Loren
03-25-2009, 11:32 AM
sounds like that could work too, but what really worries me is the self-test check the ECU does (very rich for a second, then very lean, and see how the sensor reacts. If it does not react, CEL)

though looking back at the manual's explanation, The HO2
sensor informs the ECM that the post-TWC air-fuel ratio is lean (low voltage, i.e. less than 0.45 V). That sounds like reducing the voltage of the sensor's output should be enough to trick the ECU into thinking the system is lean, thus enriching the mixture? Problem is, no way to tune that...
I'm not talking about completely faking the O2 signal and locking it down at a fixed value. It would still respond, it would just be "off" a bit, and the ECU would have no way of knowing that.

A system like the LC-1 is VERY tunable. It works like this:
Say the default narrowband O2 sensor output is .45 - 1.5 volts. (not sure if that's right or not, it's something like that) The center of that range represents exactly 14.7.

The LC-1 has not one, but TWO programmable outputs. You could wire one of them to a gauge that would tell you the ACTUAL AFR. The other one you program as a sort of "hybrid wideband" using the standard narrowband voltage range, but centered on something richer than 14.7.

The ECU sees what it expects to see (even though it's not quite the truth), the signal responds to the ECU's commands, and everybody's happy.

Now that I think about it, some additional circuitry may be required to shift the voltage range, but it should be doable. Probably way easier than hacking the ECU.

Tip: The Miata is a far, far more popular car among racers and tuners, and the factory ECU has never been hacked. The closest anyone has ever come is to overclock it with a faster crystal, which has the effect of raising the rev limit and leaning the mixture. I think asking for or waiting for a hack of the Toyota ECU is unrealistic.

eTiMaGo
03-25-2009, 11:46 AM
Right, I see what you mean, that could most certainly work too, gonna look more into that :smile:

And that's a very sobering fact about the Miata ECU, I would never have guessed!

Nexus1155
03-25-2009, 12:20 PM
http://www.allproducts.com/manufacture99/shanli/Product-2007911154234.html

probably can score that for pretty cheap if you contact them. I was introduced to the Wideband output signals from a friend a while ago, he said Zeitronix also has them on their kit just to offer an alternative to the LC1.

The SMT8 should work as well as long as it has the programmable outputs as well, this piggyback was also recommended to me by the same person who told me the AFR Gauge trick. The SMT6 that they discountinued can be found for around $150-$200
In theory it should honestly work if the ecu doesn't freak

eTiMaGo
03-25-2009, 12:26 PM
i can almost guarantee a CEL, since the ECU is programmed with safety margins and thresholds.

Yes, but, what I mean is, if you want to run a richer than stoich ratio without the ECU freaking out, you need to fool it into receiving "normal" signals.

Say that at stoich (14.7:1 AFR) the O2 sensor has a voltage of 2.5V Your target AFR is, let's say, 12:1, which would (I'm guessing) correspond to a voltage of 3.5V from the sensor. The trick would thus be to change this 3.5V to 2.5V so the ECU thinks the catalytic system is working just fine and there's no problem.

http://www.allproducts.com/manufacture99/shanli/Product-2007911154234.html

probably can score that for pretty cheap if you contact them. I was introduced to the Wideband output signals from a friend a while ago, he said Zeitronix also has them on their kit just to offer an alternative to the LC1.

The SMT8 should work as well as long as it has the programmable outputs as well, this piggyback was also recommended to me by the same person who told me the AFR Gauge trick. The SMT6 that they discountinued can be found for around $150-$200
In theory it should honestly work if the ecu doesn't freak

I guess the question now becomes, who's gonna be willing to experiment with some of these?

Loren
03-25-2009, 12:28 PM
Yeah, there are definitely other WBO2 solutions besides the LC-1, it's just the one I'm familiar with because I used it with the Megasquirt in my Spitfire.

taKuto
03-25-2009, 12:34 PM
the emanage ultimate won't modify afr signals or o2, pic i found off the web for what parameters it changes
http://www.mys15.org/S15_Tech/imgaes/wpe11.jpg

Loren
03-25-2009, 12:41 PM
What could be tried , is to take an ecu from a bigger 4 and wire it properly. If all inputs and outputs are correctly wired we can achieve wider operational range.

We should petition Denso/Toyota to open the ECU to mods without sacrificing their trade secrets.

Wouldn't work, PK.

The ECU is still going to take the feedback from the O2 sensor and tweak the AFR to stoich. It's what they do.

Now, what I don't know is... what does the Yaris do when you go WOT? Because it's an economy car, is it still trying to keep the AFR at stoich? Does it have a WBO2 stock so that it can run lean? If so, does it use that to run richer at WOT?

Most cars that I've seen that use NBO2 simply go open loop at WOT, disregarding the O2 signal and running from a map. This is surely what the Yaris is doing now that I think about it, because we can see with the ScanGauge that the car goes Open Loop at WOT.

Soooo... if we're talking about making the car run a little richer at part throttle and during cruise, the WBO2 "cheat" should work. But, it's not going to do a thing for full-throttle acceleration.

To get more fuel at WOT, you simply need to fit larger injectors and/or increase fuel pressure. What the ECU is doing at WOT is looking at RPM, air temp and air flow and looking up a fuel requirement in a table. That translates to the pulses that are sent to the fuel injectors. The ECU assumes that the stock injectors are present and flowing within spec and that the fuel pressure is within spec. If you fit larger injectors, you'll flow more fuel, but you could run out of fuel pressure if you go too large. If you raise the fuel pressure, you'll also flow more fuel.

That, coupled with a timing controller (doesn't somebody make one of those for this car?) should take care of your needs... shouldn't it?

PK, think like a large corporation. What possible benefit is there for them to put any of their resources into releasing information about their ECU? Ain't gonna happen. They want performance-minded people to spend their money buying a sportier Toyota, not buying performance parts for a Yaris.

eTiMaGo
03-25-2009, 12:46 PM
I understand the logic, but think about this , if you are fooling the ECU with "normal" levels the ECU will respond with normal levels. so if you are running lean but need more fuel and you are tricking the ecu with normal levels it won't give you the fuel you need cause it will see that there is no need for more fuel.

What we need to be looking into is raising the threshold levels. Thats what they do at the factory , lets say the 1NZ-FE is capable of 170hp with AFR of 2.1 (totally pulled out of my butt numbers for purposes of an example) , the techs lower the AFR to 1.6 and the HP drops to 106 . All it takes is a proper fuel map loaded and the problems are solved.


Yes, but this would be used in conjunction with a piggyback or even a MAF resistor trick to raise the injector duty cycle in the first place, a two-pronged approach :smile:

Well, for a non-turbo/SC'ed car, the horsepower gains from doing this would be pretty minimal, really. In ideal conditions, an engine makes peak power when the mixture is stoichical (14.7:1 Air:Fuel ratio by volume). But, with forced induction, you want to run richer as a safety margin (go read LtNoogie's thread about his lean condition)

eTiMaGo
03-25-2009, 12:50 PM
Wouldn't work, PK.

The ECU is still going to take the feedback from the O2 sensor and tweak the AFR to stoich. It's what they do.

Now, what I don't know is... what does the Yaris do when you go WOT? Because it's an economy car, is it still trying to keep the AFR at stoich? Does it have a WBO2 stock so that it can run lean? If so, does it use that to run richer at WOT?

Most cars that I've seen that use NBO2 simply go open loop at WOT, disregarding the O2 signal and running from a map. This is surely what the Yaris is doing now that I think about it, because we can see with the ScanGauge that the car goes Open Loop at WOT.

Soooo... if we're talking about making the car run a little richer at part throttle and during cruise, the WBO2 "cheat" should work. But, it's not going to do a thing for full-throttle acceleration.

To get more fuel at WOT, you simply need to fit larger injectors and/or increase fuel pressure. What the ECU is doing at WOT is looking at RPM, air temp and air flow and looking up a fuel requirement in a table. That translates to the pulses that are sent to the fuel injectors. The ECU assumes that the stock injectors are present and flowing within spec and that the fuel pressure is within spec. If you fit larger injectors, you'll flow more fuel, but you could run out of fuel pressure if you go too large. If you raise the fuel pressure, you'll also flow more fuel.

That is another avenue, yes... Gotta find the page again, but the manual did mention about the ECU going to open loop above 4000RPM, but I am not sure if that is at WOT only or not. In this case, it becomes far easier to mess around with this. This is similar to what ZPI did, whereby they put the car in a constant CEL state, which also causes it to be in open loop


That, coupled with a timing controller (doesn't somebody make one of those for this car?) should take care of your needs... shouldn't it?

Timing, as in ignition timing? another kettle of fish, yeah... Power Enterprises has the Camcon which is used to change the VVTi timing, but I don't think it does ignition, you'd need a decent piggyback to do that, I think

PK, think like a large corporation. What possible benefit is there for them to put any of their resources into releasing information about their ECU? Ain't gonna happen. They want performance-minded people to spend their money buying a sportier Toyota, not buying performance parts for a Yaris.

But where's the fun in that? :biggrin:

eTiMaGo
03-25-2009, 12:59 PM
PK, I'm sorry but this thread is not really intended to debate the way Toyota handles its intellectual property :biggrin:

eTiMaGo
03-25-2009, 01:08 PM
Toyota Canada:
1-888-869-6828
:biggrin:

Hey, it is worth a try... But I think the idea of getting the local TRD guys to look at a US ECU would be more fruitful.

eTiMaGo
03-25-2009, 01:31 PM
Aaanyway back on topic, as I noted before, it would be a good starting point to see how the Blitz controller that comes with the supercharger kit, connects to the car's wiring. I got my hand on some wiring information, and as expected, it plugs in to:

MAF sensor input
Intake Air Temperature input
A/F sensor input
Each fuel injector's output

So it stands to reason that it functions as a regular piggyback reading the various sensors and overriding the injector signals, and as Loren pointed out, this would probably only have an effect when the ECU's in open loop.

Since Long has a supercharger and a wideband installed, I'm gonna ask him to be a guinea pig :biggrin: (in the other thread about the AFR readings)

Nexus1155
03-25-2009, 01:54 PM
i actually have a spare ecu in the drawer, but its mine, if anyone has any electrical engineering background and wants to help play with it id be more than willing to drop some cash on some more R&D

ChinoCharles
03-25-2009, 02:02 PM
Not to be a downer or detract from anyone's efforts, but I think the focus of this thread should remain squarely on piggybacks. Hacking the stock ECU is great and all, but a separate working unit that will work in tandem with a stock ECU on stock settings is a much more viable alternative.

I will e-mail Perfect Power right now and get their thoughts on this. I'll post the e-mail as soon as I receive a response.

Perfect Power,

Hello. I am an owner of a 2007 Toyota Yaris in the United States. I am also a moderator of Yarisworld.com, the world's largest Yaris-oriented car forum.

I am contacting you in hopes that you can shed some light on the US market's longstanding problem with tuning Yarises using piggybacks. In short, after almost three years of the car being in the states we still haven't found one viable solution short of a standalone. AEM's FIC has been problematic at best. I know that you guys have the Yaris there in South Africa. Has the SMT-8 been a successful tuning solution for this platform? Can you offer any wisdom when it comes to tuning the tricky Yaris ECU?

If so, feel free to respond to this e-mail directly or make an account on Yarisworld.com and visit this thread:
http://yarisworld.com/forums/showthread.php?t=15350

We look forward to any insight that you may have to offer. There is a crowd of hungry tuners in the states that anxiously awaits a viable solution to this problem. If your piggyback will work with this platform, I think you can make valuable inroads into a largely untapped market.

Thank you very much.

Charles

eTiMaGo
03-25-2009, 02:12 PM
don't forget to ask what is their solution for getting around the fuel trims!

CASTREX
03-25-2009, 02:23 PM
I haven't seen "SPLIT SECOND's" name to be called on this thread yet. :iono:

These are the go to guys when it comes to tunning for the Large supercharged Toyota Engines.

Also URD (under dog Racing ) but I'm not sure if these guys actually use Split Second's stuff for their tuning devices....

Any ways, these 2 companies know their stuff on modern supercharged Toyota engines.

Not comparing the the Yaris with a Tacoma here... but still worths a shot.

http://www.splitsec.com/

www.urdusa.com

ChinoCharles
03-25-2009, 02:30 PM
Thomas, I'm no tuning guy by any stretch. You know that. What I will do is refer them to a more knowledgeable party stateside so they can have some intelligent discussion, rather than me trying to type everything they say and saying "mm-hmm" a lot.

Would anyone like to volunteer to e-mail me their contact information so I can put them in contact with PP if they respond? charlesluzar@hotmail.com

dallas
03-26-2009, 02:04 AM
That's some great team work and effort to get this stuff figured out, can't wait for some feedback.:clap:

silver_echo
03-26-2009, 02:35 AM
yes and i did get to play with it somewhat , however it was mainly for maintenance and resetting the ECU. When you first connect the diagnostic computer it asks for tech password and then gives you the option to read, write or reset. i haven't had the chance to play in write mode since i was not allowed to but the tech says when they need to program the ECU it gets either reprogrammed at Toyota factory or they get a brand new one. None of them is able to reprogram the firmware.

is the diag computer handheld based or laptop based? my thinking is that if i can get my hands on the system, i might even be able to get into mine(i am starting the toyota t-ten program soon and with me being in that program, i might be able to spend some time fiddling with the programming), and with the ECU being only slightly different, i might be able to figure it out... my basic thinking was to try to fix the rich condition at WOT, but if i can figure out how to do that, it will open it up for tuning...

ChinoCharles
03-26-2009, 08:01 AM
Hi Charles

Thank you for your email. I have forwarded your email to our Technical Team to see if there is a way to assist you. Normally the problems with certain cars are that some ECU's are really REALLY clever little units. Sometimes these ECU's detect that you are trying to intercept the signal and just don't like it and then causes endless problems. I am not too sure if this is the same with the Yaris as well but I let you know once I get more information from our Technical Team.

Kind Regards
Marcell Bruynius (Ms.)
Digital Data Systems (Pty) Ltd
Manufacturers of Perfect Power Automotive Systems
22 Arbeid Avenue, Strijdom Park, Randburg, Gauteng, South Africa, 2194
PO Box 35872, Northcliff, Gauteng, South Africa, 2115
Tel: +27 (0) 11 792 9805
Fax: +27 (0) 11 792 9818
Email: marcell@dtwebs.com (marcell@dtwebs.com)
Website: www.perfectpower.com (http://www.perfectpower.com/)

Will continue to update.

eTiMaGo
03-26-2009, 08:23 AM
sweet!
the urd afr commander or something like that, that castrex mentioned, looks quite intereting too

eTiMaGo
03-26-2009, 08:23 AM
sweet!
the urd afr commander or something like that, that castrex mentioned, looks quite intereting too

ChinoCharles
03-26-2009, 12:41 PM
Hi Charles
We have not test our products on a Yaris before but we are busy looking for one. I will let you know what is the results once we have found a car and have done the installation.
In the meantime could you perhaps let me know what do you expect from this unit i.e. more power, more fuel efficient etc. and what signals have you tried to tune in order to achieve your requirements and what was the results you got with the other units. We would just like to test these aspects as well to ensure that if the unit will be able to meet your requirements.
I will get back to you on the testing once I have more information.
Kind Regards
Marcell Bruynius (Ms.)
Digital Data Systems (Pty) Ltd
Manufacturers of Perfect Power Automotive Systems
22 Arbeid Avenue, Strijdom Park, Randburg, Gauteng, South Africa, 2194
PO Box 35872, Northcliff, Gauteng, South Africa, 2115
Tel: +27 (0) 11 792 9805
Fax: +27 (0) 11 792 9818
Email: marcell@dtwebs.com (marcell@dtwebs.com)
Website: www.perfectpower.com (http://www.perfectpower.com/)

OK guys, help me put together the response. I would suggest that Thomas make a post after this and you can help compile our data and as soon as everyone is comfortable that we have covered all of the bases I'll shoot the e-mail out. If they can conclude that their unit will work, I have a local tuning shop that uses Perfect Power's products heavily and I could be the guinea pig. I'll need a piggyback down the road anyway.

The focus of the discussion should be on power. There is a larger demand for power from tuning solutions than there is fuel economy, although I will make a point to mention that if they can improve fuel economy on a closer to stock Yaris that may generate interest as well.

largeorangefont
03-26-2009, 01:07 PM
I haven't seen "SPLIT SECOND's" name to be called on this thread yet. :iono:

These are the go to guys when it comes to tunning for the Large supercharged Toyota Engines.

Also URD (under dog Racing ) but I'm not sure if these guys actually use Split Second's stuff for their tuning devices....

Any ways, these 2 companies know their stuff on modern supercharged Toyota engines.

Not comparing the the Yaris with a Tacoma here... but still worths a shot.

http://www.splitsec.com/



www.urdusa.com


Split Second makes some cool stuff. I know those guys through some mutual friends.

Also, are there Unichips available for the Yaris?

largeorangefont
03-26-2009, 01:20 PM
I'm not talking about completely faking the O2 signal and locking it down at a fixed value. It would still respond, it would just be "off" a bit, and the ECU would have no way of knowing that.

A system like the LC-1 is VERY tunable. It works like this:
Say the default narrowband O2 sensor output is .45 - 1.5 volts. (not sure if that's right or not, it's something like that) The center of that range represents exactly 14.7.

The LC-1 has not one, but TWO programmable outputs. You could wire one of them to a gauge that would tell you the ACTUAL AFR. The other one you program as a sort of "hybrid wideband" using the standard narrowband voltage range, but centered on something richer than 14.7.

The ECU sees what it expects to see (even though it's not quite the truth), the signal responds to the ECU's commands, and everybody's happy.

Now that I think about it, some additional circuitry may be required to shift the voltage range, but it should be doable. Probably way easier than hacking the ECU.

Tip: The Miata is a far, far more popular car among racers and tuners, and the factory ECU has never been hacked. The closest anyone has ever come is to overclock it with a faster crystal, which has the effect of raising the rev limit and leaning the mixture. I think asking for or waiting for a hack of the Toyota ECU is unrealistic.

The problem with doing that is that it will probably do nothing, depending on now the open loop fueling works. I assume that the car ignores the narrowband sensor all together in open loop like most new cars do.

The chance of getting a "reflash" type solution is slim. The only hope is that the xd is popular enough to get one, and we could use it as well.

For Subarus and Evos there is open source free software to flash the ECU and make any changes you want. Unfortunately there is not that kind of demand in the Yaris market. Probably a Unichip or other piggy back is the most cost effective solution, with add on fuel and timing controllers coming in 2nd.

eTiMaGo
03-26-2009, 01:25 PM
OK guys, help me put together the response. I would suggest that Thomas make a post after this and you can help compile our data and as soon as everyone is comfortable that we have covered all of the bases I'll shoot the e-mail out. If they can conclude that their unit will work, I have a local tuning shop that uses Perfect Power's products heavily and I could be the guinea pig. I'll need a piggyback down the road anyway.

The focus of the discussion should be on power. There is a larger demand for power from tuning solutions than there is fuel economy, although I will make a point to mention that if they can improve fuel economy on a closer to stock Yaris that may generate interest as well.

urgh I'm not gonna have the time to write that up tonight, hopefully tomorrow. Plus I'd really want Garm to chime in with more details on his AEM experiences.

Also Charles, keep in mind that if they have a test car in south africa, the ECU may not be the same as yours. Seeing how seemingly easy it is for SouthEast Asia tuners to set up turbo kits, I am quite sure the US ECU is a lot more finicky.

largeorangefont
03-26-2009, 01:31 PM
The tune will increase crusing fuel economy if done correcty.

I can help with the response if needed. I'd even be willing to test it.

eTiMaGo
03-26-2009, 01:31 PM
Split Second makes some cool stuff. I know those guys through some mutual friends.

Also, are there Unichips available for the Yaris?

I've heard of several cars here and Indonesia tuned with those. But, AFAIK, their US distributor has no knowledge of it. Once again I am pretty sure due to ECU differences.

The problem with doing that is that it will probably do nothing, depending on now the open loop fueling works. I assume that the car ignores the narrowband sensor all together in open loop like most new cars do.


Yes, that seems to be the case. Open loop tuning should be far easier (as ZPI did), but for some reason looking at the Blitz'ed guys results, that doesn't seem to work too well. In other words we're really looking for a solution to cover both closed loop and open loop operation.

CASTREX
03-26-2009, 01:34 PM
Also, are there Unichips available for the Yaris?

Unichip is what all the Thai turbo Yaris are using with good success. There are a couple of Thai members with the ZAGE turbo kit using the unichip.

However, UNICHIP in the US does not show any supported aplication for the Yaris. I remeber someone from this forum contacting them a long time ago but I gues nothing came out of that...

largeorangefont
03-26-2009, 01:43 PM
I've heard of several cars here and Indonesia tuned with those. But, AFAIK, their US distributor has no knowledge of it. Once again I am pretty sure due to ECU differences.



Yes, that seems to be the case. Open loop tuning should be far easier (as ZPI did), but for some reason looking at the Blitz'ed guys results, that doesn't seem to work too well. In other words we're really looking for a solution to cover both closed loop and open loop operation.

We dont need anything for closed loop. The car is going right to open loop as soon as they get on the gas due to the increased load. When they are off the throttle crusing, the fueling if fine. Closed loop is where the ECU will fight you and "learn" around any changes you make.

You basically need full timing control, and fueling adjustment in open loop.

eTiMaGo
03-26-2009, 01:43 PM
The tune will increase crusing fuel economy if done correcty.

I can help with the response if needed. I'd even be willing to test it.

Yes, if you can start writing it up, post it here, then we can add/change what we need :smile:

As for testing, the more guinea pigs the better :biggrin:

largeorangefont
03-26-2009, 01:46 PM
Unichip is what all the Thai turbo Yaris are using with good success. There are a couple of Thai members with the ZAGE turbo kit using the unichip.

However, UNICHIP in the US does not show any supported aplication for the Yaris. I remeber someone from this forum contacting them a long time ago but I gues nothing came out of that...

There is a UNICHIP that will work, they just dont have the plug and play harness to plug the chip into the US ECU.

I have a dealer tuning kit for the Unichip, so If I could get the right chip, I could concievably make it work.

ChinoCharles
03-26-2009, 02:59 PM
Also Charles, keep in mind that if they have a test car in south africa, the ECU may not be the same as yours. Seeing how seemingly easy it is for SouthEast Asia tuners to set up turbo kits, I am quite sure the US ECU is a lot more finicky.

OK, I'll respond with that first and that will give you some time to compile your list of questions.

Marcell,

First of all, thank you for the timely and comprehensive responses thus far. It speaks well of your company and your product.

I think it is important to point out that part of the issue we are having in the US is that our ECU's are different from the rest of the world. They are a little harder to work with. There are numerous examples of successful tunes in Japan using piggybacks. We in the US have nothing but horror stories.

If South African Yarises have similar ECU's to ours, then this will work great. If not, then you may want to source a US car to do testing on. I would be more than happy to help. There is a shop in Ashtabula, Ohio called Twisted Innovations. http://www.tidyno.com They originally referred me to your company two years ago. When piggybacks came up in conversation on the forums, I decided it was probably time to reach out. If we could come to an agreement on how to handle testing the platform on my car I would have no problems with that. I have a car I can use in the meantime.

My engine has the following bolt-on accessories:
HKS Hi-power axle back exhaust
Simota carbon charger SRI
NST crank pulley
NST alternator pulley
NST water pulley
Megan 4-1 header

I have aspirations to add a turbocharger or supercharger down the line. I know your piggybacks are particularly useful in chorus with nitrous systems, so that could be an option too. I also know of various other US owners that could offer assistance. If your company is willing to help us, we're more than willing to help you.

Let me know if you believe research done on cars in South Africa will be applicable to our market. We can go from there.

Thanks again Marcell.

Charles

CASTREX
03-26-2009, 03:39 PM
Going back to the Unich topic...

The memeber using it is REVOTURBO from Indonesia

They are using Dastek unichip type Q and dastek turbo module

However they are using larger injectors and a 5th injector set up

http://www.yarisworld.com/forums/showthread.php?p=186636#post186636

largeorangefont
03-26-2009, 04:32 PM
Going back to the Unich topic...

The memeber using it is REVOTURBO from Indonesia

They are using Dastek unichip type Q and dastek turbo module

However they are using larger injectors and a 5th injector set up

http://www.yarisworld.com/forums/showthread.php?p=186636#post186636

The Unichip turbo module will support a 5th injector, so that is not a big deal. Pretty standard

aucorium
03-27-2009, 02:40 AM
OK guys, help me put together the response. I would suggest that Thomas make a post after this and you can help compile our data and as soon as everyone is comfortable that we have covered all of the bases I'll shoot the e-mail out. If they can conclude that their unit will work, I have a local tuning shop that uses Perfect Power's products heavily and I could be the guinea pig. I'll need a piggyback down the road anyway.

The focus of the discussion should be on power. There is a larger demand for power from tuning solutions than there is fuel economy, although I will make a point to mention that if they can improve fuel economy on a closer to stock Yaris that may generate interest as well.


hey guys!

i stay in South Africa , i will give this guy a call , and see what he says.

i think the US and south african yari's should have similar ECU's , so if it works on ours , should work on yours.


a friend of mine have a honda Jazz 1.5 vtec / honda fit ,he fitted a UNICHIP , and he gained 4 kw from the chip alone , so not to bad , but then again , the ECU might be different.

i'll get back to you guys.

eTiMaGo
03-27-2009, 04:45 AM
The Unichip turbo module will support a 5th injector, so that is not a big deal. Pretty standard

5th injector's a bit of a last resort solution/hack though, isn't it?

1nz
03-27-2009, 05:04 AM
greedy F-manage
he Greddy F-Manage enables you to control the feedback to your ECU, opening a range of tuning possibilities.
Features

* Controls feedback of air/fuel ratio to the standard ECU
* Does not control air/fuel ratio, this is used in conjunction with fuel controllers
* Can be used simultaneously with e-Manage Ultimate data logger
* DIP switches enable control of maps and switch on/off
http://www.nengun.com/image/catalogue/original/nengun-1977-02-trust-greddy-f-manage.png

eTiMaGo
03-27-2009, 05:23 AM
well hellooooo there! *starts reading up instead of working* arrrrgh

eTiMaGo
03-27-2009, 05:42 AM
Doesn't seem to be officially released outside of Japan, though, so good luck getting instructions in English...

http://www.trust-power.com/03electric/fmanage.html

Seems to have a NCP91 harness already, nice.

But, the million dollar question, will it be able to dance around the ECU's emissions checks...

1nz
03-27-2009, 06:08 AM
well i was told it was for new car with relearning issue, so any one got the $ and just order it already hehe because when reading this thread i think diz is the right gadget all of u been looking for

ChinoCharles
03-27-2009, 08:43 AM
Hi Charles

Thank you for sending us the specifications of your vehicle. We have managed to get a Toyota Yaris and we are going to do the installation next week. We would first like to see what the unit does on the vehicle and then we can take it from there and then talk about sending an unit out to you to try it out on your car. My manager is aware of this situation and would love to find a solution for you.

I will keep in touch and will definitely get back to you once we have done the installation and will let you know what the outcome was. What are the specification that you are after? Are you looking at fuel consumption, more power or timing?

Have a great weekend.

Kind Regards
Marcell Bruynius (Ms.)
Digital Data Systems (Pty) Ltd
Manufacturers of Perfect Power Automotive Systems
22 Arbeid Avenue, Strijdom Park, Randburg, Gauteng, South Africa, 2194
PO Box 35872, Northcliff, Gauteng, South Africa, 2115
Tel: +27 (0) 11 792 9805
Fax: +27 (0) 11 792 9818
Email: marcell@dtwebs.com (marcell@dtwebs.com)
Website: www.perfectpower.com (http://www.perfectpower.com/)

Onwards!

tk-421
03-27-2009, 01:08 PM
Onwards![/left]
[/left]
That's great news indeed! Please specify "power" as a requirement! :biggrin:

yaris-me
03-27-2009, 11:44 PM
I believe the AT and MT have different operating parameters. Will that have an affect on the piggyback?:iono:

dallas
03-28-2009, 12:54 AM
Vey promising, your the Man! Good work,

Now let's hope and prey it's not one of those African scams !

Onwards![/LEFT]
[/LEFT]

eTiMaGo
03-28-2009, 02:57 AM
OK, here's my first draft:


Marcell,

Thanks very much for your enthusiasm!

The interest in tuning our cars' fueling is primarily for use with turbo/supercharger systems. But, if there s enough flexibility and results, I am sure may would be interested in tuning for better fuel economy too.

I will quickly outline the progress and attempts at working with piggybacks fuel management systems on various US Yarii.

Some years back there was a company, Zero Point Industries, which has since gone out of business, offering a turbo kit for the car, and using an e-manage unit for fuel management. They were unable to overcome the car's closed-loop logic for tuning, and their solution was to have the car in a permanent CEL condition, where the fueling runs in an open loop, and the e-manage can have control over it. As you know, this is an extremely crude approach!

Other members of our community have tried using AEM's FIC device which is supposed to work very well, but have had many problems, usually in closed-loop mode when then ECU is fighting hard to keep the AFR in stoich. I do not have more specific details at the moment but I can ask them to provide more information if you need.

On the other hand, we have a handful of members who are using a supercharger kit manufactured by Blitz, that comes with its own fuel management piggyback unit. Not a lot is known about its exact operation, but those members who have dyno'ed their car, or have a wideband O2 sensor, have found that it is still running rather lean, even at WOT when the car is supposed to run in open loop mode.

Now, one of these members is moving to a full standalone management system, but this is really out of the skill and budget of most enthusiasts who just want a reliable way to add 30-50 horsepower to their car.

We collectively have done a lot of research into the way Toyota set up the ECU to monitor the various sensors (MAF, IAT, AF, O2) to calculate the correct injector duty cycle, and it really is a rather tight-knit system, which is great if you do not intend to tweak anything, but too smart for our own good! We have access to rather detailed technical reference (repair/service manuals) describing all of this, so please let me know if you would like a copy. Alternatively, you can check the "brainstorming" thread in our forum:

http://www.yarisworld.com/forums/showthread.php?t=15350



Feel free to add/remove/modify :smile:

eTiMaGo
03-28-2009, 02:58 AM
I believe the AT and MT have different operating parameters. Will that have an affect on the piggyback?:iono:

The AT ECU is completely separate, and apart from the different idling speed, I don't believe there is any difference at all between the ECUs

dallas
03-28-2009, 03:04 AM
Very well written, cant get more accurate and on topic than that :thumbup:

OK, here's my first draft:



Feel free to add/remove/modify :smile:

largeorangefont
03-29-2009, 02:28 AM
Sounds like you got some good feedback Charles. I would be open to testing and tuning something like this.

eTiMaGo
03-29-2009, 06:54 AM
Well after some musing about this, there are two approaches to this whole fuelling debacle.

The first one is to try to tweak the closed loop operation to run richer on demand. This is rather difficult and would hinge on modification of the AF and O2 sensors to give the ECU the impression of running lean, causing it to make the AFR richer.

The second one, which according to Long's findings, seems to be the Blitz approach (and a far more refined version of ZPI's), is to just forget about closed loop operation and trigger open loop when extra richness is required. He noticed on his Scangauge that as soon as the SC clutch was engaged and producing boost, the ECU switched to open loop

Obviously the first method would be preferred, as it should keep the car completely OBD fault-free, so in theory have no problems with inspections.

Now, looking at the reference manuals, it seems there are 3 types of open loop modes (my comments in italics):


• OL (Open Loop): Has not yet satisfied conditions to go closed loop (i.e. warming up)
• OL DRIVE: Open loop due to driving conditions (fuel enrichment) (i.e. pedal to the metal)
• OL FAULT: Open loop due to detected system fault (i.e. CEL)


So Blitz's fuel controller would be triggering this OL DRIVE mode somehow. But how? I'll report back when I find more information :biggrin:

eTiMaGo
03-29-2009, 07:40 AM
I'm looking again and again at the instructions and wiring diagram and the only input that the Blitz box has to the ECU is the MAF signal. So, the possibility is that OL DRIVE can be triggered by a MAF signal over a certain threshold. Long, does the SCII have any way to monitor MAF voltage?

eTiMaGo
03-29-2009, 07:54 AM
back on the topic of the more elegant idea of closed loop tuning, URD has some rather interesting devices that could quite possibly solve this:

AFR Sensor calibrator:
http://www.urdusa.com/product_info.php?cPath=66_72&products_id=1230100028
Tweaks the AF sensor's signal, thus affecting the short term fuel trim for closed loop mode

MAF sensor calibrator:
http://www.urdusa.com/product_info.php?cPath=66_72&products_id=1260198051
A regular piggyback style device to tweak the MAF signal to affect the fueling in open loop

MAF + Timing calibrator:
http://www.urdusa.com/product_info.php?cPath=66_72&products_id=1260198051
This ought to be enough to cover open loop operation where the timing is maxed out by default.

These products should be universal enough to work with our cars too but I am writing to them just in case, to see what input they may have :smile:

eTiMaGo
03-29-2009, 09:15 AM
Thanks Pavel, some good info there... do you mind if I post the excel file here in case anyone wants to have a look at it?

eTiMaGo
03-29-2009, 09:31 AM
well here's PK's data log of a drive in various conditions... mostly gentle driving, and you'll see several apparently random points where it goes to open loop, but looking carefully you'll see that it corresponds to the car slowing down and minimum throttle.. thus, DFCO!

can't attach excel files here, but here's a download link:

http://dl.getdropbox.com/u/691356/Normal%20Run.xls

largeorangefont
03-29-2009, 12:01 PM
Why do you guys want to do closed loop fueling adjustments? They are not needed. The car is self adjusting (to a point) in closed loop.

eTiMaGo
03-29-2009, 12:20 PM
Why do you guys want to do closed loop fueling adjustments? They are not needed. The car is self adjusting (to a point) in closed loop.

well yes but it tries to stay at 14.7 AFR no matter what. And from looking at the data that Pavel posted, the car can stay in closed loop mode even up to quite high RPMs, as long as the gas pedal is not being mashed down.

On the other hand, it is something I am not so sure about in the first place, at three quarters throttle, 4000RPM, for example, is there enough pressure from a SC/turbo that it would require fuel enrichment? Or am I barking up the wrong tree?

eTiMaGo
03-29-2009, 12:28 PM
Pavel's newest run, equipped with a heavier foot:

http://dl.getdropbox.com/u/691356/1to3Run.xls

note the relation between throttle % and open loop in the initial acceleration phase. Red numbers are shift points (hence the spot of 20% throttle which could be ignored)

largeorangefont
03-29-2009, 12:59 PM
well yes but it tries to stay at 14.7 AFR no matter what. And from looking at the data that Pavel posted, the car can stay in closed loop mode even up to quite high RPMs, as long as the gas pedal is not being mashed down.

On the other hand, it is something I am not so sure about in the first place, at three quarters throttle, 4000RPM, for example, is there enough pressure from a SC/turbo that it would require fuel enrichment? Or am I barking up the wrong tree?

That log has great info, but he is just putting around. Have him datalog a pull in a gear. Do one in 2nd from 2000 RPM and full throttle to redline, and the same in third gear. What is done to the car?

You are thinking correctly. Generally forced induction cars go into open loop sooner than NA cars. Some NA cars don't hit open loop until you go WOT. My guess is that this is one reason the Blitz SC is clutch driven, so you are not getting boost at lower load areas.

We can't see the actual AFR, but we can see his timing, which will be helpful.
Can he graph injector latency or duty cycle too? If so get that on there.

You can't hope to tune closed loop, no piggyback I have ever seen can do it. It just causes problems.

eTiMaGo
03-29-2009, 01:09 PM
LOF, I posted a second excel file just before your post with more spirited acceleration, Open Loop seems to kick in at 75% throttle and above, though this should require some more testing :smile:

I'm not sure you can get injector info off the OBD bus?

But what do you think of that URF AF sensor device I posted earlier? By tweaking the response from the sensor it would have the ability to affect the short term fuel trim and thus richen it up a little as needed. I'm just not sure how the rear O2 sensor will react to that and cause trouble...

largeorangefont
03-29-2009, 01:23 PM
LOF, I posted a second excel file just before your post with more spirited acceleration, Open Loop seems to kick in at 75% throttle and above, though this should require some more testing :smile:

I'm not sure you can get injector info off the OBD bus?

But what do you think of that URF AF sensor device I posted earlier? By tweaking the response from the sensor it would have the ability to affect the short term fuel trim and thus richen it up a little as needed. I'm just not sure how the rear O2 sensor will react to that and cause trouble...

I saw that log, he is going too slow. We need long WOT pulls in a single gear, like you would do on a dyno.

Injector info is there on the OBD, the software just needs to be able to read it.

The problem with adjusting the fuel trim is that the car will readjust it back. The car can adjust fuel trims around +/- 25% before a CEL is thrown. Like I said, I have never really seen one that truly works. The car is constantly learing around your changes.

The rear 02 does nothing in relation to fueling. It is only there to insure the pre cats are functioning.

eTiMaGo
03-29-2009, 02:04 PM
hmmm i believe those are stored values when you have a CEL, not the dynamic values like you've logged so far...

eTiMaGo
03-29-2009, 02:14 PM
right right gotcha... well this is way over my head, and I need to get to bed, so I won't be much help :frown:

Nexus1155
03-29-2009, 09:42 PM
some links i found but im in the process of reading them

http://www.autospeed.com/cms/A_2388/article.html
http://autospeed.com/cms/A_2695/article.html

largeorangefont
03-29-2009, 09:54 PM
LOF i got no engine mods so far and i need a longer straight with no one in front of me to do it safely and properly. ill try and do a run like you said from 2000k and up in each gear.

That would be great. Even seeing what a stock car does will be very helpful. Is there anything on the PID list relating to the fuel injectors?

Your list for that other pull had all the stuff we need, except for injector duty cycle or pulse width.

aucorium
03-30-2009, 01:57 AM
hey Guys

FYI , i chatted to a few guys with the SMT6 chip here in RSA, and they werent all that happy with the chip and have since changed to UNICHIP , im not sure if this is isolated senario's but just thought i'd give you guys the heads up.Problems reported are fueling and idiling , but like i said , could just be the cars that were tuned , i will keep an eye out for more info.

eTiMaGo
03-30-2009, 02:40 AM
thanks for the heads up, aucorium...

Today I tested something... As you might know I have a basic AF gauge hooked in to the factory sensor, it's not all that useful, but can show me when the car goes to open loop (in closed loop the AF ratio keeps oscillation rich-lean-rich-lean, as this is the most efficient way for the catalyser to work, wile in open loop the needle stays still). So, leaving the house, I shifted up to third at a rather low speed and put the throttle down. The engine was too low in RPMs to gain any sensible speed, but sure enough, AF needle pegged itself at 14:1 after a second, and stayed there until I let my foot off the gas.

I should have a chance to get on the highway late tonight and repeat the experiment in other gears/conditions, but this is quite promising!

aucorium
03-30-2009, 04:25 AM
mmm , that seems to show some promise , nice one!! let us know how the test goes.

aucorium
03-30-2009, 04:53 AM
FYI

i am busy researching us a Dastek Uni - Q chip , apparently this works on the yaris , it worked on my buddies honda fit 1.5 , so im gonna see if i can get a plug and play setup , as the guys here claim to have one for the yaris , i will keep you posted.

here is the chip:

http://www.dastek.co.uk/features_unichip.htm

it can control VVT aswell !

eTiMaGo
03-31-2009, 01:35 PM
here it is in excel format with in-cell bar graphs to show the relations a bit better :wink:

http://dl.getdropbox.com/u/691356/FastRun.xls

lammy29
08-17-2011, 03:54 PM
any updates after all these years?