How do I fix a hunting/surging idle that only happens when the air-conditioning (A/C) is turned on with a PFC ?

Do I need to reset my PFC and let it "learn" to idle again ?

Do I adjust the idle air screw (I really don't want to because it idles fine in every other scenario) ?

BTW: I had to disconnect the idle speed control (ISC) solenoid in order for the PFC to properly learn to idle when the PFC was first installed, and per the PFC my idle is set for 900 RPM in all three fields.

TIA,
:-) neil

PS: I will not accept "turn-off/don't use your A/C". I live in FLORIDA!

 

Experiment and learn at the same time.

 

The problem is you disconnected the ISC.....you'll either have to reconnect it or you'll have to go through the tedious process of getting the car to work right without it -- a process that Chuck has thoroughly documented in this forum.

 

Someone answer...

 

FWIW, my ISC has never knowingly been disconnected. I had Steve Kan tune it, and it will only hunt once in blue moon now . . .

:-) neil

 

I sent him my logs he is gonna look at them Monday.... I removed the 4 wires for the egr aws and split air valve but nothing idle still bounces with ac on.... I did the powerfc a/c relay but now I get cold air on all 4 settings but still bounces

 

Everything is fixed!!! All I had to do was follow the directions.... 10 min idle (without any loads) 10 min with defroster on and 10 minutes with a/c on and defroster off. It literarily took 7 to 8 minutes before the surge stopped! Let it idled for 5 minutes more then turned the car off waited 1 minute and started it again and the surge was gone"!!! So if your idle is bouncing or hunting or surging with the air conditioning on but works on all other settings all you have to do is wait... It sounds easy but all of us who had or have this problem do not like to hear the engine go crazy for longer than 1 minute or two but I was fed up and waiting a few minutes longer fixed it""""""!!,!!,!