For the past few weeks, my '97 Civic has been idling rough, almost bucking you might say, whenever I am idling and the AC is on. The AC is blowing nice and cold, and when I'm driving there are no issues. But as soon as I hit the red light the rough idling starts again, almost to the point of stalling. It feels as if the compressor is kicking on and off.
Any ideas? Thank you.

 

Check that the condenser fan (on the driver's side of the car) runs all the time with A/C on. If it doesn't, repair. When the condenser overheats the compressor puts an abnormal heavy load on the engine and eventually kicks off due to overpressure.

If condenser fan OK, clean the IACV on the intake.

 

mk378, thanks for the reply.
I suspected as much with the condenser fan. So the fan needs to be running continually when the AC is on? Assuming this is the problem, is this possibly a do-it-yourself job for someone who isn't the greatest or most experienced mechanic? Can you ballpark a price for parts if I did this myself, or what a shop might charge for this repair?
Likewise, what's involved in cleaning the IACV?
And one more thing: I'm seeing pieces of dry rotted foam flying out of the AC vents. There is an old filter that needs replacing. Where is it located?
Thank you for all your help!