I bought a 1988 firebird base model and I was going over the things and the **** for ac and heat only works on fan and doesn’t do anything if you turn on low or high. And it only comes out of defrosters It does have a kill switch to radiator fan I don’t know if that has anything to do with it just wondering if anyone has had a problem similar or knows how to fix this problem

 

This is because it isn't getting vacuum from the engine.

The little doors under the dash are operated by way of vacuum as their power source. There's a thin plastic vac line that comes through the firewall along with the HVAC wiring, near the heater hose connections. There should be a vacuum reservoir somewhere (probably the Orb Of Power in the fender well underneath the battery) and a check valve, and some lines, that go with this system. That's all messed up somehow.

The electrical problem doesn't make sense, except that the high speed blower not working is probably caused by this connector (or whatever your car's exact configuration of it... there are a few variations) being BURNT TO ASHES like everybody else's. Look for a Big Red Wire going across the firewall at the top, right below the windshield cowl, and locate this connector right about above the pass side valve cover.



Cut the red wires off as close as possible to it and replace it with a set of connectors like the left hand one in this pic. If it has a black wire (not all cars do) and it's smoked too, replace its connectors as well. Use the BIG FAT HEAVY-DUTY spade terminals in the size with the yellow barrel, NOT the little weenie crappy ones that are the same as the little weenie crappy ones with blue or red barrels. Since it has hard battery on it, you should use insulated ones if you can find them, or wrap it up real good with tape if not.

 

Thanks I’ll check the red wire I did see a lot of stuff in my engine bay is half melted