July in Florida is hot. About a month ago my 89 IROC Z28 5.7 TPI started having strange AC problems. The AC would sometimes work on start up and other times it wouldn't. When I hit a chug hole, it would always start blowing. I looked for loose wires and connectors but found nothing. Now, it has even more bizarre symptoms. My AC doesn't blow at all. If I roll a window down slightly, however, very cold air will seep from the vents. So this makes me think the compressor, evaporator, etc... are OK.
FYI, this AC has been fitted for R-134a. I would appreciate any ideas. I'll take it to the dealer if I have to. Thanks

 

blower high speed relay or its wiring

 

could be the blower motor itself too, I would think.

 

If you have no blower at any speed, suspect the motor. If only the high speed setting doesn't work, suspect the relay.

FWIW, I recently experienced the exact symptoms you describe, it was the motor.

-B

 

Hit the blower with your fist with it on. If it starts blowing you need to replace the blower.

 

It sounds like it's a blower problem and not an AC problem.

Check the grounding wire from the blower motor to where it attaches at the rear of the driver side engine head. Most likely, the bolt is not tight, the wire is degraded, causing the ground to not make good contact. When the car hits a bump or the engine moves from torque, it completes the circuit, enabling the blower motor to function.

Quick fix is to run an additional ground wire from the blower to the chassis.