i've search for several days trying to find the right post about this, but cannot fix it. 89 crx si dohc zc swap still obd0 h/e/i only. idles around 2000 during warm up, once warm drops to 1800. if i manually force the throttle to close it starts to bounce back and forth between 1000-2000. idle adjustment screw is all the way backed out to where it does not touch the throttle at all, i have cleaned the idle air control valve very well, and it did not help at all. i was able to get it to idle one time a while back during hooking my charcoal canister back up, but i dont know how to get it back to idle normal, i removed the canister once again to see if i can get it to idle, and it wont, so its back on now, and im still trying to figure it out.

 

air is entering the system around the throttle plate.

with the intake off verify that your throttle plate is full closed when the pedal isnt pressed.

spray all hoses with water in a spray bottle to search for tiny leaks, you said you cleaned the FITV on the intake manifold?

does it only do this when the engine is totally cold, or all the time, has it done it the entire time you've had the engine swapped, or only appreared recently?

 

My crx did almost the same thing and it sounds like a posable vacume leak. I found my leak with carb cleaner. Spray it a all the places where vacume could leak and if the RPMs drop thats your leak. Good luck

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 90crxdriver &raquo;</TD></TR><TR><TD CLASS="quote">My crx did almost the same thing and it sounds like a posable vacume leak. I found my leak with carb cleaner. Spray it a all the places where vacume could leak and if the RPMs drop thats your leak. Good luck</TD></TR></TABLE> Yes try this