A/c idle problems...92 vx please help
 

So My A/c works fine.. New condenser and compressor. My problem is that I have two Civic vx's and one when you hit the a/c button it will hick up the idle to about 1100rpms but on my other one it will idle barely 250rpms. Some times it stalls when I push the clutch in... FYI when A/c is off it runs and idles fine.. So is there a sensor that tells the throttle to go up when a/c is turned on??
Please help jesscairns@yahoo.com or post a comment:confused:

It's done by software in the ECU. Actually idle should be 750 with A/C off and 800 with it on. (Don't trust dash tachs to measure idle accurately). When the A/C is engaged the ECU opens the IACV more. So if the IACV is sticky or clogged (including the passages in the manifold) it may not be able to get enough air into the engine and keep idle rpm up. You may also need to open the air screw on the top of the throttle body, but not so far that idle is too high with A/C off.

Do make sure that the condenser fan works-- with the fan inoperable, the high side pressure will go crazy, causing the compressor to pull too much hp and bog down the engine.

Ok so Im in TX where its been over 100 deg for 65 day... The a/c is full and gets cold but it seem that me fan isn't keep enough air moving throw the condenser, but it is always running. Its seem that it can get ride of the heat fast enough...
for example:: If it really hot out and it pours rain out it get super cold fast in the car even through the temp out side didn't go down..
The IACV is clean and almost new, and like I said it runs and idles perfect without the ac on...
What do you think????:eek:

Anyone else having this same problem?? I just don't think it can get rid of the heat fast enough.. Will a aftermarket fan that pushes more CFM help, or should I just get a new fan because there only $80 new...? The idle problem may still be there but I might have to replace the ECU to fix that...

"The A/C is full..." Of how much of what? R-12, R-134a, some mixture, snake oil, air, etc?

You should get both pressure readings and see if the problem is that it's pushing too much high side pressure, or if the A/C is indeed working normally and there is a problem with the engine, perhaps as simple as a dirty / stuck IACV.