Throttle lag and response - Toyota Yaris Forums

yaris-me · 03-03-2009, 02:40 AM

I bought a PLX Kiwi. I've been using it in sensor mode. I discovered tonight that there is a throttle lag and it does not open beyond 81%. No matter how much I floor it it won't go beyond 81%. On acceleration it will pause, go to 50%, pause and then 70%, then to 80%. On passing there is that same pause. I would like to say half a second to a second, but I'm guessing.

I know it's DBW (drive by wire), but this is a big lag. Also, it doesn't open beyond 81%. This can only mean that DBW is preventing full performance of the engine. Do you think this is true?

ddongbap · 03-03-2009, 03:26 AM

Is this true untill redline?

yaris-me · 03-03-2009, 03:34 AM

I couldn't take it to redline, but first to third it shifted on its own at full throttle. I was on Broadway and later on Magnolia. I'll play with it some more tomorrow.

ddongbap · 03-03-2009, 03:35 AM

Yea, I don't think its normal. If 81% was normal, you'd still hit redline, you know what I mean?

yaris-me · 03-03-2009, 03:47 AM

I didn't have enough road to really open up the throttle. I'll have to try again on the freeway.

My initial feeling was that the DBW and engine management computer is preventing me from damaging the engine. If this is true then being able to reprogram the computer would allow you to gain more HP and better performance.

2006fronty · 03-03-2009, 05:45 AM

Would the Blitz throttle controller help with the 81% throttle issue? or does it just open the throttle faster getting to the 81% limit SOONER? It seems like it would help with the lag with the DBW though.

TOUGEghost · 03-03-2009, 08:18 AM

Quote:

Originally Posted by yaris-me

I discovered tonight that there is a throttle lag and it does not open beyond 81%.

I noticed the same thing on my car. I've heard of the same issue on other DBW cars as well.

cali yaris · 03-03-2009, 06:12 PM

The Blitz unit changes the curve but not the top limit, I think.

I've heard this post before about it not opening up past 81% -- curious.

yaris-me · 03-04-2009, 02:53 AM

Quote:

Originally Posted by ddongbap

Is this true untill redline?

Tonight I tried some more. I have an AT. When the water temp reach 172, I started to floor the gas. First to second it shifted at 5400 and later at 5800. Second to third shifted at 5800 and later at 6000. Third to fourth shifted at 5800 and later at 6000. After a while, the highest shift point was 6100, third to fourth. The ECU never allowed me to redline the engine and the throttle never went beyond 81%

The throttle lag is gone. I think the ECU is adaptive and after a while it eliminated the lag.

IllusionX · 03-04-2009, 10:07 AM

in an automatic, i belive the ECU is able to detect your load and shift accordingly to that.

try to sit 4 in the car and do the same test again. i'm 99% sure it will shift closer to redline. At least, this is what i noticed with my 93 swift. Alone in the car, I always wondered why it would always shift at ~4000-4500rpm until one day we were 4 in the car and going on an incline... it went all the way to redline before shifting..

YarisPR · 03-04-2009, 10:18 AM

ANy ideas on a manual?

yaris-me · 03-04-2009, 01:43 PM

Quote:

Originally Posted by YarisPR

ANy ideas on a manual?

I think the ECU determines maximum engine output. The ECU would probably limit fuel after 6000 RPM preventing you from damaging the engine. I think this would apply to manual also.

IllusionX · 03-05-2009, 05:10 PM

the redline is somewehre around 6250rpm.

i got to the cutoff a few times.. it's around 6500rpm. i would love to have a scangauge to know the real answer to this...

1NZYaris1 · 03-05-2009, 07:28 PM

Scangauge reads the same max throttle 80%

PETERPOOP · 03-05-2009, 07:34 PM

dun dun dun!

blktiger60 · 03-05-2009, 07:50 PM

Quote:

Originally Posted by IllusionX

the redline is somewehre around 6250rpm.

i got to the cutoff a few times.. it's around 6500rpm. i would love to have a scangauge to know the real answer to this...

No point in waiting till 6500 RPM's to shift. That's well past the power range.

Manual:
On the freeway today, on my way to work, I downshifted to 3rd floored it to 5800 and slapped it into 4th - plenty of acceleration. I didn't notice any latency. I know for a fact I can smoke the stock tires in first and get a chirp from second. Doesn't feel like DBW to me.

TOUGEghost · 03-05-2009, 09:06 PM

I wasn't complaining about any lag, but 80% throttle with the pedal all the way down does bother me.

DogetorHue · 05-02-2017, 07:41 PM

I know this is an old thread, but it would seem that the ECU is intentionally limiting throttle response. Take a look at this graph from one of the manuals...

03-03-2009, 02:40 AM	#1
yaris-me Learn to Relax Drives: 2007, Meteorite, LB Join Date: Dec 2008 Location: Anaheim, CA Posts: 2,070	Throttle lag and response I bought a PLX Kiwi. I've been using it in sensor mode. I discovered tonight that there is a throttle lag and it does not open beyond 81%. No matter how much I floor it it won't go beyond 81%. On acceleration it will pause, go to 50%, pause and then 70%, then to 80%. On passing there is that same pause. I would like to say half a second to a second, but I'm guessing. I know it's DBW (drive by wire), but this is a big lag. Also, it doesn't open beyond 81%. This can only mean that DBW is preventing full performance of the engine. Do you think this is true?

03-03-2009, 05:45 AM	#6
2006fronty Drives: 2010 Mazda3 iTouring Join Date: Jun 2007 Location: San Bernardino Posts: 234	Would the Blitz throttle controller help with the 81% throttle issue? or does it just open the throttle faster getting to the 81% limit SOONER? It seems like it would help with the lag with the DBW though. __________________

03-03-2009, 06:12 PM	#8
cali yaris ULTIMATE View User's Garage Drives: 07 Yaris Turbo Join Date: May 2007 Location: Canoga Park, CA Posts: 14,859	The Blitz unit changes the curve but not the top limit, I think. I've heard this post before about it not opening up past 81% -- curious. __________________ Micro Image forums, online store and shop are now closed. It was a great eight year run, but it was time to focus on other things. I'm still selling parts on eBay under micro*image seller ID and customers can still make requests for anything specific.

03-04-2009, 10:18 AM	#11
YarisPR Drives: Yaris Sedan Join Date: Sep 2006 Location: MayaWest, Puerto Rico Posts: 1,574	ANy ideas on a manual? __________________ I Drive a 129whp Yaris ;)

03-05-2009, 07:28 PM	#14
1NZYaris1 View User's Garage Drives: Yaris Join Date: Oct 2008 Location: New Zealand Posts: 2,566	Scangauge reads the same max throttle 80% __________________ http://www.microimageonline.com/forums/index.php

03-03-2009, 03:26 AM	#2
ddongbap Banned Drives: yw calls me douche and racist. Join Date: Aug 2007 Location: hay Posts: 2,183	Is this true untill redline?

03-03-2009, 03:34 AM	#3
yaris-me Learn to Relax Drives: 2007, Meteorite, LB Join Date: Dec 2008 Location: Anaheim, CA Posts: 2,070	I couldn't take it to redline, but first to third it shifted on its own at full throttle. I was on Broadway and later on Magnolia. I'll play with it some more tomorrow.

03-03-2009, 03:35 AM	#4
ddongbap Banned Drives: yw calls me douche and racist. Join Date: Aug 2007 Location: hay Posts: 2,183	Yea, I don't think its normal. If 81% was normal, you'd still hit redline, you know what I mean?

03-03-2009, 03:47 AM	#5
yaris-me Learn to Relax Drives: 2007, Meteorite, LB Join Date: Dec 2008 Location: Anaheim, CA Posts: 2,070	I didn't have enough road to really open up the throttle. I'll have to try again on the freeway. My initial feeling was that the DBW and engine management computer is preventing me from damaging the engine. If this is true then being able to reprogram the computer would allow you to gain more HP and better performance.

03-04-2009, 10:07 AM	#10
IllusionX It's the illusion you see View User's Garage Drives: 07 Yaris Sedan Aero Join Date: Oct 2006 Location: Brossard, QC Posts: 3,888	in an automatic, i belive the ECU is able to detect your load and shift accordingly to that. try to sit 4 in the car and do the same test again. i'm 99% sure it will shift closer to redline. At least, this is what i noticed with my 93 swift. Alone in the car, I always wondered why it would always shift at ~4000-4500rpm until one day we were 4 in the car and going on an incline... it went all the way to redline before shifting..

03-05-2009, 05:10 PM	#13
IllusionX It's the illusion you see View User's Garage Drives: 07 Yaris Sedan Aero Join Date: Oct 2006 Location: Brossard, QC Posts: 3,888	the redline is somewehre around 6250rpm. i got to the cutoff a few times.. it's around 6500rpm. i would love to have a scangauge to know the real answer to this...

03-05-2009, 07:34 PM	#15
PETERPOOP View User's Garage Drives: 08 white liftback Join Date: Oct 2008 Location: Oahu Posts: 3,674	dun dun dun!

03-05-2009, 09:06 PM	#17
TOUGEghost Mr. Clean View User's Garage Drives: 2009 Yaris S 3-Door Join Date: Nov 2008 Location: Kauai Posts: 268	I wasn't complaining about any lag, but 80% throttle with the pedal all the way down does bother me.

05-02-2017, 07:41 PM	#18
DogetorHue Drives: 2009 Silver Yaris Sedan Join Date: Feb 2015 Location: The Moon Posts: 2	I know this is an old thread, but it would seem that the ECU is intentionally limiting throttle response. Take a look at this graph from one of the manuals... Attached Images