I have an 86 TA 305 TPI. The previous owner removed the A/C components but kept the wiring and the firewall box. When the key is turned to "Run" without starting the engine, the A/C lever in the dash can move thru all the settings and works fine. The blower works and the levers and suction sounds are there. Start the engine and have it running and the blower works on vent and heat but pops the fuse on everything else. I've checked the wires and grounds in the engine compartment but must be missing something. The kid before really hacked this thing up. Could be alot of problems.

 

I had a similiar problem on my Iroc , it turned out to be a bare wire going to the compressor was arcing and causing havic with the a/c unit. I got the ole electrician tape after it. It was right on top of the compressor , I guess it melted from the heat of it.