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after changing my timing belt to a gates one, the car struggles on idle. let me explain...

i believe my belt is done up too tight. (someone correct me if im wrong)

first cold start, will rev low, struggling to stay alive (sometimes dies), belt is cold, and the motor is working hard to keep the engine alive.

once the engine warms up, belt is slightly loosen and warm, and the idle returns back to normal.

i adjusted the aac valve on cold start to keep the engine running normal under 1000rpm instead of struggling at 400, but once the belt is warm, my idles revs is high above 1000rpm

i thought after a few k's she will settle in and be ok. however i have done 5000kms since then.

now, after getting a new clutch today, i said to the mech can you have a quick look at my idle.

he didnt look into the tension, however said the idle motor is not working. pulled the plug off and the was no change in the idle.

after searching this site, i can not find the "idle motor" plug thing. was hoping for a DIY fix. can someone help me out?

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I would be more looking at whether the CAS was installed back in the right position after the belt swap or ensure that the timing belt was installed correctly and hasn't skipped a tooth.

How is the car driving other than the idle problem?

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at first, it did have a missing tooth. however was rectified.

car drives normal, have hammered it and drives as per usual.

timing is set 15degrees.

what is the idle plug the mech speaks about?

Idle air valve and Auxiliary air valve are at the back of the plenum. The brown and the purple plugs. Cant remember which is which but those are the ones you want to be looking at.

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Yeah you could give it a clean out. But usually when something goes wrong after a big job like a timing belt install, the problem usually lies with something to do with the install. The odds of the IAC starting to act up at the same time a timing belt was done is highly unlikely.

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at first it was installed incorrectly.

skipped 3teeth.

they gave it back to me like that. no torque, back firing, unable to rev, stalling. was horrible. return it and they solved it. however idle has not been good.

and i know those plugs now. ones that connect to the damn aac. idle motor?.. hahah

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at first it was installed incorrectly.

skipped 3teeth.

they gave it back to me like that. no torque, back firing, unable to rev, stalling. was horrible. return it and they solved it. however idle has not been good.

and i know those plugs now. ones that connect to the damn aac. idle motor?.. hahah

yeh thats those. Check the CAS like phil said first, coz that is ALWAYS a problem

If he said he has removed the idle plug and it had zero affect on the idle then you may want to see why.

Take the plug off and put your multimeter on it and check for any signal.

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The thing is if the car is stationary, idleing and warmed up, unplugging the plugs doesn't necessarily change anything.

The AAC can be unplugged without doing anything since there is no extra load on the engine from power steering etc that requires the AAC to open up.

The IAC can also be unplugged if the engine is at operating conditions without doing anything since once again there is no need for it to open up.

I don't remember if the stock ECU detects them some how being unplugged and changes anything though. Easy way to find out get some one with a stock ECU to unplug them but I think the same theory will apply.

Edited by PM-R33
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The thing is if the car is stationary, idleing and warmed up, unplugging the plugs doesn't necessarily change anything.

The AAC can be unplugged without doing anything since there is no extra load on the engine from power steering etc that requires the AAC to open up.

The IAC can also be unplugged if the engine is at operating conditions without doing anything since once again there is no need for it to open up.

I don't remember if the stock ECU detects them some how being unplugged and changes anything though. Easy way to find out get some one with a stock ECU to unplug them but I think the same theory will apply.

Ah ok, I thought he meant the mechanic unplugged the IAC while the car was still warming up.

Have you yourself tried unplugging the IAC while the car is warming up or did you just take the mechanics word for it?

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