AC Not Working at Idle

first thing i was gonna say is pull out your gauges and check your pressures but that shouldnt matter if the truck is idling or full bore. Never had that issue before so im subscibing to see what others say would cause that situation

 

High preassure switch, it’s on the ac dryer

 

Does your fan come on when the compressor stops? The reason it doesn't cool when idling is because the fan is supposed to come on and the compressor is supposed to stop when the freon pressure is high.

Does the fan come on at all? This could either be an AC problem or an engine fan problem.

 

Omg ... people ....

Op clean the condenser.

Loosen it all up so you can get some medium pressure air and blow it out from the back to the front. Then do the same thing with the radiator and ACA to clean all the crap that has accumulated.

Pretty sure this will fix your problem, it should be done ever couple years anyways.

 

He said it isn't turning on the engine fan.

 

It’s probably the high pressure/ fan switch on the air drier, as others have mentioned, If I’m not mistaken, it’s a bianary ( Double) switch. Sounds like the fan half of the switch isn’t working. It’s the one on top of air drier with a short harness/ pigtail on it. The other switch is low pressure switch.Its good, otherwise compressor wouldn’t come on at all. If Replacing the bianary switch doesn’t get the fan working. You have another problem somewhere else. Fan selinoid maybe? Either way fan should come on when idling and compressor should also cycle off. Till pressure drops. Staying on longer than off , even on the hottest days. Hotter temps and higher humidity causes higher pressures, causes more cycling.Overfilling system will also cause it to cycle off for too long. Sounds like you have a fan problem. Make sure condensor and radiator fins are all clean for good air flow. So the fan can do it’s job, pulling air through fins, once it’s fixed.Simple answer change bianary switch, simple 7/16 wrench and a plug. You won’t lose any Freon in the process.Unscrew old switch slowly.

 

gauge it

 

put paper clip in the plug. see if it comes on. but truly need to gauge it