A/C Problems...

[cummins_crewcab]

In my 03 with 84k on the clock the A/C is just not working too well... It works great on the highway but around town it never gets cold and when sitting a red light for a while the compressor actually turns itself off... Are there known problems with the 03 A/C systems or am I just unlucky again?

 

[ROCKJEEP]

Both of out trucks did the same thing. My buddy has an ac shop here in my bussiness coplex and he fixed both of them. They were both low on charge. He toped them off and the freeze me out. They were both almost a pound low. If your ever in the riverside area let me know and he can look at your truck

Kory

 

[sag2]

Sounds like your fan is not working correctly. If the charge was way low, the high side pressure would never get high enough to shut off the compressor. If I remember correctly, it shuts off about 460 PSI. With the A/C off, block off the radiator with a towel or fender cover, and see if you can get it hot enough for the fan to start roaring when you rev it up and pull off the air flow restriction. With the ambients in the valley this week, it should get hot enough in a couple of minutes at 1500 rpm or so if you start the test with a fully warm engine.

 

[Prairie Dog]

Really low pressure will also cause a switch to shut down the compressor so that it doesn't get damaged.

 

[frijole]

Low on charge

I'm no armchair cowboy, but it sounds like you're short on charge. Seldom the condenser/radiator fan is the problem. The discharge air (per the manual), should be 45*F, (used to be 38-40*F in previous years). If your compressor is cycling off before the t-stat cycles it, it's most likely going off on low pressure. These systems don't hold much refrigerant, so any loss is significant. Get it serviced asap, or you run the risk of burning up the compressor, which is suction gas cooled. With the truck parked, run the idle up to 2K rpm and grab the suction line with your hand and the inside fan on "recirc". The line should be cold, (prox 45-50*F) under that condition. Ron