Idle Fluctuates; Temperature

[shaohaok]

just give a couple of revs when it's doing that, usually stops it

i also think the main cause is the AFM design.

[georgec]

funnily enough, my car runs fine when it is cold, but once up to running temp it farts and idles funny and shakes...... took it to toyota and they reckon they cant make it play up... probably cos they started it at 7 in the morning and ran it for about 30 seconds and then turned it off..... such a comprehensive service department....

the running temperature nature of this problem is making me think that it may be an o2 sensor somewhere or something like that playing up.... but the toyota computer doesnt pick it up and neither does my bf's diagnostic computer at his workshop  <_<

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The issue you describe Jade could very well be a lazy O2 sensor. One that will not throw an error code, but certainly affect the idle and low throttle opening performance (when in closed loop operation).

Pippy on the other hand is unlikely suffering from an O2 sensor problem because on cold start and cold running, the O2 sensor signal is ignored until the engine reaches a certain operating temperature.

Pippy's problem may in fact be a suspect vehicle speed sensor signal. When the engine is cold, the engine idle speed is constantly being adjusted by the ECU to ensure proper operation however when on deceleration, the ECU sees a high engine speed without a corresponding vehicle speed - deducing that the engine idle speed is high - and driving the idle stepper motor to close the throttle. When you do finally come to a stop and depress the clutch, the idle speed drops and the ECU drives the idle stepper motor up quickly causing the high engine speed. It overshoots and drives the stepper motor back down quickly – and then up again etc causing the idle speed to hunt.

When the engine is at normal operating temperature, the ECU essentially reverts back to a set idle position and does not drive the idle stepper motor - hence Pippy's normal idle when the engine is warm.

Hope this helps.

gc

[obsessionz]

That is so true!! mine does it only when its cold .. so what can we do to fix this problem ?? my cars still under warranty let me know plz ....

[Otaku]

Hi all. I'm suffering the same issue as the original poster. It hasn't bothered me too much, but I'll definately bring it up at my next service seeing as my car is still under warranty.

Slightly related; how long do you let your car warm up before driving? Is that a common thing?

I'll see what I can find out about the idling issue through work.

[Otaku]

I spoke to a number of people in Technical Services Operations who attempted to search for any FTR's related to the problem, as well as a gentleman from the dealer helpdesk. Unfortunately it turned up nothing related to our problem. The best advice I got was to monitor the vehicle and take specific notes when the issue occurs, such as your driving condition prior to the issue, the weather conditions, engine temperature, air conditioning system status, etc. to try to make it as repeatable as possible. The most significant step in trying to have the problem fixed is to physically reproduce the issue for the dealer.

[obsessionz]

Most of the corollas have this problem ... who ever has it should keep calling toyota eventually they will have to make a fix for this problem ... an fix all the corollas... Im sick of it too..

[Rolla Boy]

Could possibly be air lock in the cooling system also...

[Otaku]

The only way it will be escalated through Toyota is for more FTR's to be lodged.

[xoom]

The only way it will be escalated through Toyota is for more FTR's to be lodged.

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Guys as stated previously when trying to get other issues resolved.... Unless everyone pays their dealer a visit no action will happen as it will be assumed that this is a unique case and toyota wont spend anytime trying to resolve it..... Simply coming to the forum and trying to get it resolved is not enough .... Also simply saying to toyota that there are many others with this issue because u see them discussing it on the forum is also not enough because they will check on ur claim and if they find only 1 or 2 other complaints that does not warrent an investigation..... I have learnt in dealing with toyota it turely is safety in numbers

[obsessionz]

COMON GUYS EVERYONE KEEP CALLING UP AN COMPLAININ I WANNA GET THIS********* FIXED ... WE CAN DO IT!!!

:P

[Otaku]

COMON GUYS EVERYONE KEEP CALLING UP AN COMPLAININ I WANNA GET THIS********* FIXED ... WE CAN DO IT!!!

:P

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Dude, don't waste your time. Like I've been trying to tell you, and like xoom reiterated, engineering and production wont do anything / wont even find out about your problem if you simply keep ringing up Toyota. Taking your rolla into your dealer with a clear record of the conditions that cause the problem, so that they can reporoduce it themselves will likely get a Field Technical Report raised (as yet there is not a single one for this issue).

When the FTRs start building, the issue gets escalated, and something will be done about it.

You might as well save your phone money.

[jade]

i am going to do the throttle body coolant bypass this weekend and see if that makes a difference.... my car only does it when its warm, so hopefully this may make a difference..... <_< at this point i am willing to try anything as my warranty is out of date now...

[Otaku]

i am going to do the throttle body coolant bypass this weekend and see if that makes a difference.... my car only does it when its warm, so hopefully this may make a difference.....  <_< at this point i am willing to try anything as my warranty is out of date now...

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Cool, let us know how it goes.

[obsessionz]

Will Changing the ECU to a performance ECU ? fix this problem let me know ??