2003 tahoe a/c problem
 

The a/c on my wife's Tahoe will not blow cold air when idling either at a redlight or otherwise. The truck has 116,000 miles and runs like a spotted ape! Had Freon checked and guy said it is good.

When we are running the a/c will freeze your a$$ off. What causes it to not blow cold air when idling?

This is typical for most vehicles.

Most A/C will not put out cold air until the engine is running above 1000 rpm's.

The compressor needs to run fast enough to compress the freon to have a higher pressure drop across the expansion valve. The expansion process cools the freon so that when the air passes over the cooling coils....the air gets cooled.

I hope this makes sense.

also check the condenser if its mounted behind the grill to make sure its not full of bugs and road debris.... if it is clean it

Same problem with my car

Low engine coolant will also cause this

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Clean the condenser coil as said and check that the compressor clutch is engaging at idle if not your low pressure switch could be bad

Its the fan. Electric or clutched its all the same. Its alwats the fan when its this symptom

Cheap fix

Maybe on a Chebby but not on my car. (Ford)

There is a valve in the compressor that gets stuck. (refridgerant control valve) You can replace that valve and it should fix it. I don't know how to recover and recharge the system that's why I haven't fixed mine yet. I took it to the shop and they me i need a new compressor. I don't think that's true, if I needed a new compressor then it would not blow cold at all....... am I right.

Yes

But I'd still check the fan first. If no air is being pulled then it won't cool the car. Once you start driving and air is flowing thru the coils it starts blowing cold again........Fan everytime

I'll check out the fan Dink but I'm 99% certain its running. I did a goodle search on my problem and it's very typical of this model year car to have this problem.

How do you remove the refridgerant from the system and recharge it. Is it difficult to do?

Call me

I agree with Dink. Sounds like a fan issue. Setting still, no air flows through the coil but does just fine when moving. I also had a similar problem a few years back with a 99 Sierra. The compressor was "coming apart" inside and sending metal filings to my orifice valve, expansion valve whatever you call it. The filings would of course clog the thing up and the pressure would build to a point that when I wasn't moving, the compressor would cut off. When I was moving it worked just fine.
But check the fan first.

thanks, guys!

Swamp snorkler what they'rewas most likely talkin bout is a pop off valve. Its a pressure release valve mounted on the compressor. It releases freon if pressures get too high and most cant be replaced without replacing the comp. As far as the original problem for both you guys it more than likely is a fan issue. Some systems have a primary fan (for the engine cooling system) and a secondary fan (for the a/c system) and just because you here a fan humming doesnt mean they're both working. High La. temps and humidity play heck with a cars a/c system. Deal with it everyday at work during the summer. A restricted condensor or a resticted orifice tube/expansion valve will cause a spike in head pressure and poor to no cooling but driving at hwy speeds rarely causes good cooling in that case.

I had the same issue with Mine. My compressor clutch wasn't engaging. Took it to a shop and they recharged the system and put fresh oil fo the compressor, and it worked fine.