Idling like an F1 car
 

wow this just popped up out of nowhere.. my car idles around 1500 rpms now. I've also had a weird hesitation problem for a while, could the iac be causing this? Any way to test it? I don't even know where it's located..

You mean the 1500rpm idle like when the car first starts up? Normal operation is cold start, idle at 1500rpm until at standard temp, then it drops to 300-400. I would check your TPS voltage, make sure it's as close to .5v as possible.

If you shut it off, then restart it, does the idle correct itself?
If so, then it is likely the TPS

TPS....no doubt about it

but how does the tps go bad it's mechanical, I've torn it open before and there's nothing to it.
It idles like that warm and cold.

Any check engine light codes?
Sounds more like something is sticking.:confused:
You can try cleaning the tps.

Same problem... well, mine sticks at 2,000 sometimes a little over, and it takes like forever to come down to 900, but if I gitve it some gas it will go up again.... plus I still have that rough running issue :confused:

check engine light comes on sometimes when I first start the car.. then it'll be gone for days at a time. Maybe I'll hookup with budfreak sometime, he's around this neck of the woods..

The contacts corrode and get crud on them, thus they don't read the proper resistance along the entire path.

If you've had it apart before, do it again and use some good electrical contact cleaner.

It actually looked brand new when I looked at it last time, about 5 months ago..

The throttles are shut at idle and the required air is supplied via a separate circuit. When the engine is idling the throttles are bypassed via an idle air circuit. Provided the TPS is delivering the correct signal voltage, (0.5 volts) when the throttles are shut, and they are mechanically shut, there can be no adverse affects. This can be simply tested, as per my advice included within the how too stuff.

When the engine is cold, idle air is provided via the by-pass air control solenoid valve, together with the auxiliary air control valve. The latter is directly temperature operated and should shut as the engine warms up. The solenoid valve is controlled via a signal from the ECU, which depends on several sensors for the required information in order to set the idle speed for various conditions, when the engine is at normal running temperature.

A diagnostic check should show up any of several possible faults, with the exception of the auxiliary air control valve, which is a very likely culprit. If this does not shut when the engine becomes warm, idle speed will be excessive, as is the exact symptom reported. N.B. There is a constant 12 volt supply to this valve, even though it is not involved with the TCU.

An air leak post throttles, could also cause the problem. There have been reports of loose manifold bolts. However in view of temperature being a reported factor, this is a less likely cause.

I hope this screed may be of some assistance. ;)