Idle high after boosting for a while.

[playitlouddsm]

Ok, i've looked around on all the posts and threads about idle surge and other idle problems and their possible remedies but haven't really seen anything written up about my problem. The car will idle just fine when first started, but after driving around for 10 miuntes or so the idle will gradually rise up to 1500 rpms and stay steady there, then a few miuntes later it will rise again to around 2000rpms and stay there. Any ideas on how to solve this problem will be greatly appreciated.
Thanks, Nick

 

[RossY]

There is a bracket that bolts the throttle cable to the top of the intake manifold. When i rebuilt my car i made sure there wasn't much slack in the line. Needless to say i had the same problem, the car idled great when i started it but after a bit the idle would slowly rise. So i popped the hood and cracked the two bolts loose that hold the throttle cable to the intake manifold. As soon as i did that idle instantly dropped down to where it should be. I guess the reason for the problem was that the metal was expanding when it got hot and would pull the throttle partially open. I hope that helps

 

[PaleDSM]

Next time the car is idling high pop the hood and force the butterfly on the throttle body closed. If the idle drops you can be pretty sure that it is in your throttle or cruise control cables.

 

[playitlouddsm]

There is a bracket that bolts the throttle cable to the top of the intake manifold. When i rebuilt my car i made sure there wasn't much slack in the line. Needless to say i had the same problem, the car idled great when i started it but after a bit the idle would slowly rise. So i popped the hood and cracked the two bolts loose that hold the throttle cable to the intake manifold. As soon as i did that idle instantly dropped down to where it should be. I guess the reason for the problem was that the metal was expanding when it got hot and would pull the throttle partially open. I hope that helps

Thanks alot man, you were exactly right

 

[RossY]

no prob, its nice when its just a little prob that causes a headache.