Cold A/C ... only when moving

[bkboatnsleds]

I have a 2003 Tahoe - manual HVAC system.. I get cold AC but its only when the truck is moving - if I come to a stop light, it starts blowing warm air at me. Thoughts? I could be on the expressway for 2 hours.. blowing cold and then stop and warm air starts..

I also have a 2002 Yukon doing the same thing -but it seems after driving a while I can then come to a stop light and it will still blow cold..

Thoughts??

 

[LinuxMint]

Needs to have the freon refilled maybe?

 

[Freedom Motorsports]

I agree, take them in and have the AC recharged...

 

[gitrduun]

Wash out your radiator and tranny cooler and shit, the condenser is in the mix somewhere and if you don't get flow over it from a plugged up rad ,it'll give symptoms like yours

 

[afpj]

Do you have the belt driven fan? look at your fan clutch. Had same issue and cleaned out radiator (from the outside, although a flush may not hurt either) and changed the fan clutch...now blows cold at a stop even when 110 outside.
Good luck and let us know what you did.

 

[Vinniety]

Do you have the belt driven fan? look at your fan clutch. Had same issue and cleaned out radiator (from the outside, although a flush may not hurt either) and changed the fan clutch...now blows cold at a stop even when 110 outside.
Good luck and let us know what you did.

I agree with the fan clutch. When driving the air is cooling the condenser. When your stopped the fan is suppose to do the job and it sounds like it isn't. No matter how much freon you put in it wont get cold if the condenser gets heat soaked.

 

[ScottyBoy]

Fan clutch. Thats the first sign of a fan clutch going out. AC getting warm will be the least of your worries if you do not replace it. You don't want your engine overheating and end up causing damage. Just replace the fan clutch and while the fan is off, hose out the radiator fins from the engine side (like suggested above). You will be surprised how much dirt , leaves, and dead bugs will come out of the fins.

 

[streetscraper1]

If it were your fan clutch your engine temp would be getting hotter than normal, I say you just need your freon level topped off. Just have somebody hook up some guages and check your high and low pressures.

 

[ScottyBoy]

If it were your fan clutch your engine temp would be getting hotter than normal, I say you just need your freon level topped off. Just have somebody hook up some guages and check your high and low pressures.

Not always. The fan clutch can still be partially working. Like I said in my post above, warm AC only at idle is the first sign of a fan clutch going bad.
I am not saying the refrigerant isn't low, but DO NOT simply rule out the fan clutch just because your coolant temp hasnt gotten very high yet.

 

[streetscraper1]

^^ what he said!