Hello guy, I have searched for the answer but I could not find it. First of all my A/c is not charged, but thats not the problem. When I move the climent controls to a setting with ac at idle everything is fine. But when i just tap the throttle a bit the engine revs to 2000 rpm and will stay there until i turn the ac off. As long as I dont hit the throttle it stays at 750 rpm. Could this be a vacuum leak at the climent controls? My car is a 84 z28 camaro with the L69 engine. Thanks in advance

 

I was thinking maybe a vac leak in the controls but what puzzles me is that the rpm is fine unless I tap the throttle. It happens in all gears including park

 

Heh heh. Easy one. The A/C idle compensator solenoid is a little solenoid on the front/side of the carb that pops up the idle speed when the A/C is turned on. Doesn't matter if the A/C is functional or not. It pushes on the front of the throttle arm of the carb.

SHouldn't go to 2000 RPMs, though. Sounds like it's pushing too far. Should take it to maybe 1000 RPMs or so. Pop the electrical connection (one wire) off of it and it won't happen any more. Front, driver's side of the carb. If you have plans of fixing the A/C some day you should work on adjusting it to give the A/C-on idle speed specifed for your particular year/model/engine per the underhood emissions/tuning sticker.

You'll probably ask: Why doesn't the idle speed pop up as soon as you turn on the A/C???? The solenoid doesn't have the strength to push the throttle arm forward on it's own. Once you tap the gas, however, it pops forward and locks in place, elevating your idle RPMs from that point on.

 

hey thanks man, it works! I can now drive and adjust the climent comtrols without fear of the car taking off on me
Thanks

 

I bet the RPM climbs so much because the speed was set with the system working, draging the engine down, now without a load on it the engine runs too fast.