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Hey guys! My name is Jimmy and I'm a fanatic!

I'm also new to the site so I'm not entirely sure this is where I should be posting this. That being said...

My car revs on its own, like it can't wait to go fast! When I turn it on and leave it on "Park" the RPM's go to about 2.75-3 and stay there for about 30 seconds and then come down to about 2.25-2.5 RPM's. The only way it goes down to sub-1 RPM's is if I put my beautiful gal in "Reverse" or "Drive."

I have no idea what's going on! I was hoping I could get some help here as some time of rummaging through the internet has led me here.

Thank you in advance!
 

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Hatch Nation #136
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Idle air control valve. It is located on the intake manifold between the manifold and the block. They get clogged up and stick.

Another thing to check for would be vaccuum leaks, but a racy idle is usually the IAC.

You should be able to pull it and clean it. There's a pretty good how to for it on the site.
 

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Idle air control valve. It is located on the intake manifold between the manifold and the block. They get clogged up and stick.

Another thing to check for would be vaccuum leaks, but a racy idle is usually the IAC.

You should be able to pull it and clean it. There's a pretty good how to for it on the site.
What he said.
 

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You might want to reset your PCM (the computer) as well. Now you do realize that revving up to 2k rpm or so is normal for a cold engine. If allowed to remain in N or P, the idle will slowly drop down to where it should be in N or P which is about 1k rpm or a little less. Now if this is happening when you put your car in P after driving somewhere, then it is a problem. There are 2 idle settings for your vehicle- one for N/P, and one for in gear.

Now on to cleaning the IAC- here's sort of what it looks like:


To reset the PCM, I personally do this with a warm engine to reduce the amount of time it takes for the engine to warm up to normal op temp, remove the negative battery terminal for 10 mins or so. Now reconnect the battery terminal, and start the engine without touching the accelerator. Allow the engine to idle for 6-7 mins. What happens is that the PCM performs a 5 min timed test to determine the optimal A/F ratio once the engine is warmed up. If you have a tach, you should see the idle settle to about 1k rpm, and fluctuate slightly. Once the test is finished, the idle will settle down to it's normal speed which should be just under 1k rpm for an auto in P/N. If you touch the accelerator, the test will start over.
 
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