I have a 2003 Silverado SS with just over 80,000 miles on it. I have owned it since it had 9,000 miles and I have always noticed that at idle or in stop and go traffic the air conditioning either blows warm air or air that just isnt as cold as when Im moving. I plan on taking it to the dealer but was wondering if anyone else has experienced this problem.

 

a/c pump wont be turning as hard at idle, might be why

 

not enough airflow over the condenser so pressure builds and the compressor shuts off to keep the system from exploding

 

The high pressure cut out switch doesn't open until like 450 psi on most systems. Its just there to keep the compressor and lines from blowing to pieces.

In most cases the high side pressure just gets higher then it should be and the system becomes very inefficient. Air conditioning is all about heat transfer.

I would say pop the plastic piece off the top of the core support that covers the radiator and condensor and look down in between the two and see how much trash is in there. Usually a garden hose is sufficient enough to wash one out or a blow gun and a good air compressor works too. My rule of thumb is if it will suck a sheet of paper against the grill and hold it then its pulling enough air across the condensor. Could be a weak fan clutch.

 

on my 03 ss the a/c works with out the ac button pushed, the condensore runs all the time, but if i press the a/c button i dont get any air , maybe thats your problem

 

Seems like around 2002 for whatever reason they started keeping the AC on with just the recirculate being on. My dads truck always did this. My 99 even with the recirculate only on will not turn the AC on. The AC button has got to be on before it comes on, or on defrost.

 

The problem is airflow related like Atomic stated. Install some electric fans and it will help it out.

 

X2!,

could have a bad fan clutch, install some electric fans they help alot

 

Ill have to check the radiator when I get home from work.

Ive always planned on installing e-fans but I want the easiest plug and play option possible.

 

+1...and as mentioned above, this will cause less air flow across the condenser. I will admit though, my truck used to blow slightly warmer at idle or in traffic, but since I installed the 05 Efans it's ice cold all of the time. My 96 Blazer, which has the factory clutch fan, blows noticably warmer at idle, and it's clean between the rad and condenser, as I replaced the radiator recently and cleaned any junk out of there. Fan clutch is good too...it's just the nature of the beast in some cases.