I recently bought a 1997 3.8 standard. I was told the a/c expansion valve needed to be replaced to get the air to blow cold. The compressor is good and it vents warm air only. I am not sure if I am looking for the expansion valve or an orifice tube?

 

Have you tried having it filled with refrigerant? Common cause of warm air blowing with A/C is little or no refrigerant. Buy some that has the dye in it and get the light and glasses so you can check for any leaks while filling. Most auto parts stores will have a kit that includes everything.

 

Does the compressor clutch operate when you switch on the A/C? If not, you have other problems than an orifice tube. Conditions that prevent the activation of the compressor include low refrigerant charge, A/C trouble codes, and low idle speed.

Your 3.8L has the VDOT A/C compressor. That has an orifice tube (VDOT=Variable Displacement Orifice Tube). That allows the compressor to stay on all the time without cycling. The 5.7L V8 car has the type with the thermostatic expansion valve and that requires cycling.

 

Yes I have tried refrigerant and I used a gauge it says its full. Still no cold air. I do not have much knowledge of the a/c system. I turn the a/c on when and the car doesn't sound like there is a change in the idle. I am not all sure how to tell if the clutch has engaged on it.

 

Watch the front of the compressor. With the clutch off, you can see the pulley rotating but not the clutch, which is in the front/center of the assembly. With the clutch on, both parts will be rotating.

 

Okay, the clutch does engage when the a/c is turned on. What should I look for next?

 

I just took a look at the condenser and it is really dirty and has a bunch of tiny rocks in it. I may need to replace it but could it be clogged and that is the reason why it doesn't blow cold?

 

If the condenser was clogged preventing air circulation, the engine would be overheating seriously.
Is the air coming in cold at first and then gets warmer over time? Or is it warm from the start?
The P/O could be right about the orifice tube. Have an A/C shop do an estimate. I have heard that the VDOT compressors are difficult to charge properly (high side only??)

 

It just blows warm from the start. The system is full too.

 

Not necessarily. It depends on how far he drives it in one trip. If he only drives 5 miles or so to go to work or such, his car isn't even going to be running long enough to show an over heating situation.

There is the possibility that the system is over filled or even the evaporator is clogged.