Chevy aveo revs too high at start and idle

chevrolet
aveo

#1

I drive a 2004 Chevy Aveo. My car normally idles at about 800 rpms but the last two days, whenever I start my car, the engine has reved up to 2000-2500 rpms and stayed there. When I put the car in gear (either reverse or drive) the rpms drop to a little over 1000. When idling in drive it continues to idle at over 1000. If I shift back into neutral or park the rpms jump back up to 2000+. I had this same problem sporadically last winter but never had it checked out and then the problem disappeared over the summer. Now it is getting colder again and the problem is back! Any thoughts/suggestions??


#2

It is normal. You’ll notice that after the engine has warmed up the idle is back down to 800ish rpm.


#3

I wish it did! Unfortunately, even if I have been driving the car for a while and the temp gage says that the engine has warmed up, the car still idles high and the rpms still jump back up to 2000+ once I put the car in park.


#4

Is the idle high and steady? Or high and uneven? If the former, open the hood and find your idle air control (IAC) valve. Its mounted right on the throttle body somewhere. While it is idling poorly give it a sharp whack with the handle of a hefty screwdriver or something like that. If this changes the idle, clean the IAC valve and if that doesn’t help replace it.

If the idle is high but uneven then you probably have a vacuum leak - find it making sure to include the intake manifold in your checking.