I got my 92 xtra a cpl days ago and the a/c works, but every now and again randomly itll start making an awful screeching noise... only to be fixed by letting off the gas a bit, hitting the a/c button, and then turning it back on... i havent been able to pinpoint exactly what triggers it, im thinkin either compressor, or the compressor belt... hopefully just the belt any ideas?

 

The noise is most likely the belt slipping. it's probably caused by a combination of RPM, other loads on the belt (PS, alt), and the shock load of the compressor clutch (think dropping the clutch vs tires) Try a new belt. If your 92 still has a manually adjusted AC belt, try tightening it just a little...don't go too crazy or you'll mess up the bearings in the pulley

The compressor usually won't screech but grind, same for the compressor clutch.

 

Nice thanks yeah i was leanin towards the belt slipping, but wasnt too sure if there were any common problems i didnt know about... ill try tightening it a bit and keep my fingers crossed