The AC on my 98 TA has worked great for the three months I've had the car -- vent-thermometer shows an output somewhere between 38-42 degrees even in the August heat here in Texas.

Tuesday morning was something new here: the temperature outside dropped into the 50s, and I had to run the heat to defrost the windows.

Tuesday afternoon, get in the car to go home from work, and the AC isn't blowing cool. Thermometer says the air from the vents is slightly warmer than the outside air (outside - mid 80s, vents - low to mid 90s).

The compressor clutch is not engaging. Using EFILive, selected the option to force the clutch on, and the clutch did engage but the air did not get cold.

I had a spare set of the AC controls, put them in but it did not help. Temp **** appears to adjust heat correctly. The selector-switch does turn everything off when set to "off" and does select floor/vent/defrost correctly.

So -- what's the next step in troubleshooting?

 

Put a set of gauges on the car and tell us what they say when you get the clutch to engage and compressor to turn on. This weill help you more than anything else.

 

And the gauges really do tell all. 0 psi on both sides tells me I've got a large hole I've got to find and fix.

Thanks!