High idle at start

[Black '93]

Has anyone experienced a higher than usual idle at start-up on an ATX? Especially at cold starts, my car initially revs to about 1900 RPM instead of the usual 11 or 1200. the idle doesn't fluctuate up and down, and in drive the RPM is fine. Also when I park my car, it goes up to aboout 1300 RPM... Any ideas?
Thanks.

 

[Ishodu]

Could be vacuum leak, have you had any part of the intake apart or off the car? You can check all the lines around the intake and what not to see, you may also hear it with the car running with the hood open.

 

[CerberuS]

Could be vacuum leak, have you had any part of the intake apart or off the car? You can check all the lines around the intake and what not to see, you may also hear it with the car running with the hood open.

Good tip also is to spray carb or brake cleaner around vacuum hoses and intake while engine on., if theres a leak the engine is gonna change sound if you sprayed in a leaky area.

 

[Black '93]

I did just do new valve cover gaskets and intake gaskets, but I am sure there are no leaky hoses. I have been looking everywhere for a leak and found nothing. The idle does die down to normal RPM after a bit, but like I said, the idle is higher than normal, yet completely smooth and the car doesn't die or anything...

 

[CerberuS]

Still there might be a smallish hole where the intake sits (new gaskets?)

same with hoses , sometimes you cant see the tiny hole.

 

[Black '93]

I triple checked all of the hoses, and even removed the intake again to check the hoses going to the secondary controllers and all of that... Yeah new gaskets.

 

[NotSoSlowSHO]

Before you tear anything else apart, try a simple idle reset.

I assume that when you did the valve cover gaskets, and intake manifold gaskets you had the battery unplugged?

If so, and if you havnt done an idle reset, then the EEC just hasnt been able to relearn idle.

 

[Black '93]

Actually, this may sound funny but I never even unplugged the battery during the whole thing because I wanted to listen to music and have no stereo in the garage. I did disconnect it at the end but probably didn't do the reset correctly... I'll try that tonight.