Idle issues

Addicted2Boost · Post by **Addicted2Boost** » Wed Jan 19, 2011 3:58 am

I recently reverted back to the stock ECU and plugged back in the IAC it was not used when I was using MS. I had used the adjustment screw to control idle when not in motion.

The problem im having is at a complete stop the car idles at about 800 rpm. but when in motion the car wants to idle at 1500-2000 rpm, even if i push in the clutch while in motion it will idle high until I come to a complete stop then the car will resume 800 rpm once stopped. Im not to sure why its doing this any suggestions? everything is plugged in again. The throttle is not as responsive as it was when i physically unplugged it.

Addicted2Boost · Post by **Addicted2Boost** » Wed Jan 19, 2011 6:10 am

I tried adjusting the screw but it didnt really do much besides adjust at stop idle

Danteneon · Post by **Danteneon** » Wed Jan 19, 2011 8:36 am

The IAC motor needs to be cleaned (I've seen this several times). The pintal gets hung up instead of closing like it should allowing the idle to hang.

Remove the IAC and using some non-clorinated brake cleaner and an old toothbrush, clean all the old carbon out from it. Re-install and be happy again

Post by **occasional demons** » Wed Jan 19, 2011 9:43 am

If that doesn't work, you may need to mess with your idle stop some more. Try backing it down until the throttle plate is closed, but does not stick. The TPS voltage being too high at idle will cause the high in motion rpm's. You are effectively increasing/lowering the voltage by adjusting the stop.

It should idle @1000 rom while in motion. The IAC will take care of the idle even with the throttle plate sealed. It might need a few miles to adjust itself.

ZeroChad · Post by **ZeroChad** » Wed Jan 19, 2011 12:00 pm

I vote vacuum leak.

Post by **occasional demons** » Wed Jan 19, 2011 12:27 pm

It wouldn't return to 800 rpm. I have messed with the TPS voltage, and it does exactly this. In motion idle jumps way up.

Addicted2Boost · Post by **Addicted2Boost** » Wed Jan 19, 2011 1:09 pm

I have brake cleaner will that work?

Danteneon · Post by **Danteneon** » Wed Jan 19, 2011 1:18 pm

It will, but it's better if it's non-clorinated. It will be easier on the rubber parts inside than the clorinated ones. You should be fine as long as you stay away from carb cleaner.