94 camaro with 3.4L, it has 240K miles. its idling at 1200 rpm's with no check eng light on. anyone have an idea on where to start. vacuum leak? i checked for split hoses and tightness of the lines but nothing is obvious. i cleaned the EGR valve out about a year ago. its not a daily driver, any ideas? thanks in advance.

 

Head up to local parts store to get a free code scan done. Sounds vac leak tho,computer adding fuel to compensate for leak,engine light should be coming on

 

well it may just be a combo of the miles your guage may be off does it idle down I know my 3800 at start idles down from 1150 to 800 ,is it higher at start then at idle down meening is at like 1500 at start then down to 1200 sound like vacuum leak ,though cars that old an those many miles ,not sure I would be concerned

 

Its getting air from somewhere. If you are brave you can plug the idle port in the throttle body with your finger. The engine should stall. If it does you have an issue with you IAC motor. If it still runs then it is getting air from someplace else.

Clean the IAC (search your tube for how too video) spray carb cleaner all around the intake and hoses, if the idle changes then track down that leak.

 

thanks everyone, i will do the carb spray trick and see if the rpm's get higher and take out the iac and clean it up. i can add that when the a/c is on, it drops the idle to around 1k, which is about where it was before. its definitely idling higher. shifting is a little hard (5 sp manual) cause the rpm's are up there.

 

an up date:

i took the air cleaner off and started her up. i put my hand on (and covered the whole throttle body) and it stayed running. it obviously dropped the idle a lot. looks like i am looking for a massive air leak somewhere.

 

You are not looking for a massive leak. The hose leaking to the Brake booster alone can put you at 3000 RPMs with no load.

Common failures are the large hose coming off the throttle body and the brake booster hose both will crack and it may not be visible.

 

yep start pulling hoses and blocking the intake/suction side. see which one makes it slow.