I've always wanted a Jetfire just because it's an early factory turbo application. Does the Starfire have a new fangled engine like a 215 or odd fire V6? Does it have the tranny in the rear like the early Tempest?
I suspect the Klima or low pressure switch acted up and they bypassed it completely rather than more subtley (is that a word?) with a similar relay at the Klima socket.
Step 1 is to determine if there's a PBU ground signal at the low pressure switch behind the left headlight. There'll be a couple of switches attached to the drier. One will have a couple of spade connectors, the other will have a couple of pigtails. We're after the one without pigtails. One wire comes from the PBU, the other goes to the Klima socket behind the battery. Find the PBU wire and test for ground when the compressor should engage.