Abysmal perfromance of 2005 Vitz RS

[SlowVitzRS]

Hello,

Recently purchased 2005 Vitz RS in manual.
We have multiple 1NZFE powered vehicles in family but they are either Auto or CVT.
Although the car is not for me, but compared to the car it replaces the performance is abysmal.

Before buying I have driven multiple Vitz RS and they all were gutless.
As comparison my 2002 Toyota IST (also 1NZFE powered) does not have this asthmatic feel. I cannot really compare the CVT Vitz RS as the transmission completely masks the engine performance.

BTW the vehicle this Vitz RS meant to replace is a very worn Toyota Trueno 20 valve.

It is a bit disappointing that Toyota stuck "RS" label on such slow car. What is even more disappointing that the fuel economy is not far off the 20v (8L/100km around town).

Unfortunately there is nothing like that here (New Zealand) on the market (Manual small hatch).

What puzzles me is that 2002 IST (1NZFE) has better throttle response (no lag) and revs freely right through to the redline, while the Vitz RS (1NZFE) has very slow throttle response and bogs down after about ~5000rpm.

Before anyone says this is not a sports car, tell that to Toyota with their "RS" badge.

Right now I am planning to do the following:

Check/Replace air filter
Check/Replace spark plugs (the car has done 60000kms, so theoretically spark plugs are still ok)
Clean MAF
reset ECU and go for a spirited drive
Change oil to Motul 0W30 and genuine filter.
Check O2 sensor operation (should not affect WOT operation, but might affect long term fuel trim?)

Anything else I could check?

Disclaimer: yes I admit that almost every car on the road will be slow to me (I drive WRX STI), but I am comparing this car to Toyota IST and Toyota Trueno.

[SirDigby]

it might be the issue of switching from a cable driven throttle body to a drive-by-wire system. I was disappointed with this too when I first purchased my car. do some reading on "1zz-fe throttle body swap." it makes a huge improvement in response and top end flow. it is very simple to do if you own a drill and have access to some 5mm bolts and nuts. (and a junk yard)

why are you using 0w30?

also, look inside of the air box lid. (the top) idk how they do it in NZ, but in the US there is a built in, non-serviceable charcoal filter plastic riveted to the top. take a screwdriver and pop that turd out to increase flow. there is also some good DIY's on box trimming!

[SlowVitzRS]

it might be the issue of switching from a cable driven throttle body to a drive-by-wire system. I was disappointed with this too when I first purchased my car. do some reading on "1zz-fe throttle body swap." it makes a huge improvement in response and top end flow. it is very simple to do if you own a drill and have access to some 5mm bolts and nuts. (and a junk yard)

why are you using 0w30?

also, look inside of the air box lid. (the top) idk how they do it in NZ, but in the US there is a built in, non-serviceable charcoal filter plastic riveted to the top. take a screwdriver and pop that turd out to increase flow. there is also some good DIY's on box trimming!

Thanks for that, I will look into 1ZZFE throttle body and gutting out the airbox. My NCP61 IST definitely has louder induction noise, and is more responsive.

What is wrong with using 0w30? Most likely the car was filled with 15W40 mineral oil before hand (whatever was in the barrel at the shop that serviced it). I use 5w30 in my STI without issues (and sometimes 0w40).

I cleared out the MAF sensor (it had little bit of fluff, but nothing excessive) and went for spirited drive, which seemed better (but nothing to write home about).

BTW Vitz RS is a JDM import, in NZ they were sold as Echo (1st gen) and Yaris.

[Bluevitz-rs]

it might be the issue of switching from a cable driven throttle body to a drive-by-wire system. I was disappointed with this too when I first purchased my car. do some reading on "1zz-fe throttle body swap." it makes a huge improvement in response and top end flow. it is very simple to do if you own a drill and have access to some 5mm bolts and nuts. (and a junk yard)

why are you using 0w30?

also, look inside of the air box lid. (the top) idk how they do it in NZ, but in the US there is a built in, non-serviceable charcoal filter plastic riveted to the top. take a screwdriver and pop that turd out to increase flow. there is also some good DIY's on box trimming!

You're mixing up your facts.

'05 was the last year for cable throttle. It wasn't until the new model in '06 that brought about all the changes to engine management including throttle by wire and emission related stuff like the charcoal filter inside the airbox.

A cold air intake frees up a LOT of power on the first gens. But you can tap a few by removing the induction pipe from the airbox. It has a small inlet restriction at the end to limit noise.

[SlowVitzRS]

You're mixing up your facts.

'05 was the last year for cable throttle. It wasn't until the new model in '06 that brought about all the changes to engine management including throttle by wire and emission related stuff like the charcoal filter inside the airbox.

A cold air intake frees up a LOT of power on the first gens. But you can tap a few by removing the induction pipe from the airbox. It has a small inlet restriction at the end to limit noise.

Regarding fly-by-wire or not, it is definitely fly-by-wire.
Last 1st gen was made in Jan 2005 and first of 2nd gen was made in Feb 2005.
I have 2nd gen (NCP91).

As comparison between fly by wire systems, my STI is also fly-by-wire, but I have no problems with throttle response (even though it is turbo).

[SirDigby]

there is also a few companies that make a "throttle box" that plumbs between throttle pedal and wiring harness. it "modifiys" the signal sent frm the throttle pedal to create more response. there is usually 3 or 4 different settings.
here is one that gets good reviews: Sprint Booster
https://www.sprintboostersales.com/How-It-Works.cfm

WRX is a performance car, so it's ready to perform.
Yaris/Vitz is an economy car, so it tries to go as slow as possible (even though it's badged RS)

[SlowVitzRS]

there is also a few companies that make a "throttle box" that plumbs between throttle pedal and wiring harness. it "modifiys" the signal sent frm the throttle pedal to create more response. there is usually 3 or 4 different settings.
here is one that gets good reviews: Sprint Booster
https://www.sprintboostersales.com/How-It-Works.cfm

WRX is a performance car, so it's ready to perform.
Yaris/Vitz is an economy car, so it tries to go as slow as possible (even though it's badged RS)

The point is that from 1st gen 1NZFE to 2nd gen 1NZFE there is noticeable degradation. There was no need for Toyota to turn a fun car into a Lada.

1ZZFE powered Corolla? rocket ship compared to Vitz RS
2AZFE powered plane boring Camry? not so boring compared to Vitz RS

I am not even talking about 2ZZGE powered Corolla, or 2GRFE powered Camry ;).


I am afraid to think that Civic might have been a better choice (the problem is hard to find a manual variant).

From toyota perspective making such crappy tune out of capable engine is a big mistake especially in cars with manual transmission. People who are genuinely after economical car would buy CVT.

I should put our CVT Vitz RS against our manual Vitz RS and see which one will be faster (I have a feeling that CVT will win).

[IllusionX]

If your trueno had a 4A-GE, I can tell you right away it's the reason why you Vitz feels sluggish.

Sent from my SM-G930W8 using Tapatalk

[SirDigby]

the 06+ civic is nice because of the EEPROM on the CPU can be easily re-flashed, but the exhaust hole on the r18 is such a terrible design. (imo) the SI is nice, but because of how they thinned the gears to make the 6 gears fit there is a lot of failures on 3rd gear. also, the civic is like 1000 lbs heaver and more expensive. the 1zzfe is easily swapped into the yaris if you want to go that route too. I hear the 2zz will fit with minimal modifying to the frame rail, if you're ambitious. corolla brake swap is pretty easy too...

[ncp13]

Which transmission does it have? You need the C56 transmission .

If I am correct the VitzRS is the NCP91 and it should have the close ratio transmission. It should not bog down at 5k.. it should bounce the rev limiter at 190kmh on fifth gear at 6500rpm.

You should verify if it is an original RS NCP91-AHMVK

Verify the compression on all 4 cylinderes 213psi max, 156 psi low and max difference pere cylinder 14psi.

If your compression is ok procced to the regular maintenace items!

If not propably the piston rings are stuck. ( pm me )

Do an engine flush and use 0w-30 PFE ( diesel spec :) ) Cleans gunk out and can take 17:1 compression on its oil film.


Check intake for restriction and clean out the MAF sensor on the airbox.

Do the ECU reset you mentioned

Good luck !

[thebarber]

05 with drive by wire? i doubt that.

take a pic of the engine bay or the car...

[WeeYari]

05 with drive by wire? i doubt that.


IIRC, what we know and love as the Gen2 introduced as MY2006, was earlier introduced in Asian markets as a MY2005. OP is in New Zealand.

[enviri]

^much as how the 3rd gen is introduced here in 2012, but in japan in late 2010.

[SlowVitzRS]

05 with drive by wire? i doubt that.

take a pic of the engine bay or the car...

It is JDM and definitely drive by wire.


I just bought one 1NZFE throttle and one 1ZZFE throttle, will combine them and replace original to see if it is any better.

Will post pics once have the chance.


Which transmission does it have? You need the C56 transmission .

If I am correct the VitzRS is the NCP91 and it should have the close ratio transmission. It should not bog down at 5k.. it should bounce the rev limiter at 190kmh on fifth gear at 6500rpm.

You should verify if it is an original RS NCP91-AHMVK

Verify the compression on all 4 cylinderes 213psi max, 156 psi low and max difference pere cylinder 14psi.

If your compression is ok procced to the regular maintenace items!

If not propably the piston rings are stuck. ( pm me )

Do an engine flush and use 0w-30 PFE ( diesel spec :) ) Cleans gunk out and can take 17:1 compression on its oil film.


Check intake for restriction and clean out the MAF sensor on the airbox.

Do the ECU reset you mentioned

Good luck !

It is original RS, and I have driven multiple of them and all of them were sluggish. Other people also reported this.

At this stage I am not going to bother with compression as the slowness is repeatable across multiple cars. The engine inside is pristine: there is no sign of sludge what so ever, so I doubt piston rings are stuck. Besides it has only done 60000kms (37000 miles in freedom units).

Yes, definitely Motul 0w30 oil next oil change.
Already cleaned the MAF sensor, it freed up the midrange a bit.

[SirDigby]

wow you bought both? that's crazy. do you have to do emissions testing? if not you can get some pretty aggressive cam shafts. (and as always, forced induction) there is a few good lightweight flywheels available out there. the exhaust has 2 catalytic converters, and the second one is not monitored. exhaust work frees up some pep. removing the back seats and rails frees up quite a bit of weight, depending on your passenger needs.

[SlowVitzRS]

wow you bought both? that's crazy. do you have to do emissions testing? if not you can get some pretty aggressive cam shafts. (and as always, forced induction) there is a few good lightweight flywheels available out there. the exhaust has 2 catalytic converters, and the second one is not monitored. exhaust work frees up some pep. removing the back seats and rails frees up quite a bit of weight, depending on your passenger needs.

I would like to retain car as stock as possible ;).
There are no emission testing in NZ (crazy!), just a visual check.

[ncp13]

Mine has the factory 15inch rims and stock size tire and 180000km and it revs out without hesitation :confused:


I dont know the weight difference of a NCP13 with a NCP91 maybe it gained a few kilos..


Stock factory figures where 0-100km/h 9 sec and 190km/h at the limiter :rolleyes: and about 107bhp.

I would still check for compression though as I am weird like that :smile:

[SlowVitzRS]

Mine has the factory 15inch rims and stock size tire and 180000km and it revs out without hesitation :confused:


I dont know the weight difference of a NCP13 with a NCP91 maybe it gained a few kilos..


Stock factory figures where 0-100km/h 9 sec and 190km/h at the limiter :rolleyes: and about 107bhp.

I would still check for compression though as I am weird like that :smile:

Well, my wife's IST (NCP61 same gen as your NCP13) is fine as well.

Will see how it (vitz rs) behaves with 1ZZFE throttle body...

Regarding compression: there is no need to check it, as it does not consume oil, there is no blow by, there is no idle issues, oil is clean etc.

What I believe has happened is that Toyota was lazy and used the same CVT safe tune/throttle map on manual car. While throttle response on CVT equipped car is not important on manual car it is somewhat important (unless you hate driving).

If I wanted a boring car I would have bought an automatic Tiida for half price.

Regarding performance difference between two - yes Gen2 is slower than Gen1 due to 80kg difference (Gen1 950kg vs Gen2 1030Kg). This difference would not explain anaemic throttle response.

What I am saying is that toyota took all the fun out from the engine with their very conservative tune. Bloody 3 cylinder Sirion is more fun to drive than this thing.

[ncp13]

Well if emissions is not a problem in NZ maybe you should backdate your ecu and throtle to gen 1 :)
Or try those kits that remove the lazynes from the systems with e-throtle.

Good luck :smile:

[SlowVitzRS]

Success!

The 1ZZFE throttle body conversion fixed the throttle response and power drop after 5k rpm.

Here is the write up:
http://sergei.nz/toyota-vitz-rs-and-its-disappointing-throttle-response/

[invader166]

Success!

The 1ZZFE throttle body conversion fixed the throttle response and power drop after 5k rpm.

Here is the write up:
http://sergei.nz/toyota-vitz-rs-and-its-disappointing-throttle-response/

Great write-up! Really informative.

If you're not looking to get a new intake manifold, you could also buy a throttle body spacer, and shave it a bit to match the diameter of the 1ZZ throttle body. Sadly that would also mean having to get longer hoses...:frown:

http://www.ebay.com/itm/X714-A-THROTTLE-BODY-SPACER-for-2006-to-2015-TOYOTA-YARIS-1NZ-FE-/272517091875

[SlowVitzRS]

Great write-up! Really informative.

If you're not looking to get a new intake manifold, you could also buy a throttle body spacer, and shave it a bit to match the diameter of the 1ZZ throttle body. Sadly that would also mean having to get longer hoses...:frown:

http://www.ebay.com/itm/X714-A-THROTTLE-BODY-SPACER-for-2006-to-2015-TOYOTA-YARIS-1NZ-FE-/272517091875

I am looking at getting a spacer cut out of 6 or 8mm alloy plate and have slope ground in the opening to match two diameters in a gradual fashion.

[SirDigby]

I made my own spacer. it was a pain, but it turned out awesome and it was fun! (no longer hoses required)
http://www.yarisworld.com/forums/showthread.php?t=55767
http://www.yarisworld.com/forums/showthread.php?t=56265

and you should port your manifold. or you can buy mine in April when I sell it.
http://www.yarisworld.com/forums/picture.php?albumid=1179&pictureid=6102
http://www.yarisworld.com/forums/album.php?albumid=1179&pictureid=6101
http://www.yarisworld.com/forums/picture.php?albumid=1179&pictureid=6100
http://www.yarisworld.com/forums/picture.php?albumid=1179&pictureid=6103
http://www.yarisworld.com/forums/picture.php?albumid=1179&pictureid=6104
http://www.yarisworld.com/forums/picture.php?albumid=1179&pictureid=6105
http://www.yarisworld.com/forums/picture.php?albumid=1179&pictureid=6107

[ncp13]

I am thinking that maybe your throtle body was defective and not opening as much? :confused:

I have tried 1ZZ cable throtle body on my 1nz and I did not see much.I lost low end throtle response and it was happy at high rpm.

Its great that you got the power back. :biggrin:

[SlowVitzRS]

I am thinking that maybe your throtle body was defective and not opening as much? :confused:

I have tried 1ZZ cable throtle body on my 1nz and I did not see much.I lost low end throtle response and it was happy at high rpm.

Its great that you got the power back. :biggrin:

Nope, throttle was not defective (otherwise it would thrown a code).
What actually is wrong in my opinion is not the throttle size, but throttle map. the 1ZZFE throttle due to size simple overrides map as 70% opening might as well be 100% (compared to original). Toyota gimped too much the throttle map.
I can bet I would got the same result with a throttle controller.

With manual throttle if you give it 100% it is guaranteed to be 100%. With drive-by-wire not so much. Drive by wire were introduced because this way they can reduce emissions during transients (ie when you plant your foot down suddenly), and smooth out torque curve to make it more flat (at expense of peak power).

[SlowVitzRS]

A follow up:

I discovered that on cold the idle would shoot up to >3k and sometimes would oscillate.
There also was an occasional harsh overrun transition.

Since then I have made a plate up and fitted between the 1ZZFE throttle body and 1NZFE manifold, this serves two purposes:
1) Ensure the O-ring seals properly
2) Provide a smooth transition between two diameters.

To remedy the oscillation I turned adjuster screw 3 times counter-clockwise.

Here is the write up:
http://sergei.nz/toyota-vitz-rs-throttle-swap-sorting-out-bugs/

[SirDigby]

yeah that's pretty high. I turned mine until it was idling at like 1800. I turn it wile the engine was running. at warm idle it was at like 450, and it threw a check engine light. I would bump the screw about 1/4-1/3 of a turn at a time until the check engine light stayed off. took like 2-3 times to get it right. at very cold it will start at 2400 for about 3 seconds, then drop to 2000-2100. after about 20-30sec it will drop to 1600-1800. at full warm idle is 550.