Ratchet23

Hi I have a 91 firebird 3.1 and I bought it for just under $500 and of course that means its a project and of course that means headaches and apparently cold drives to school. Well I drew the line today when with wind chill it felt like -7 this morning 👎⛄. So most of the time I put it on full blast in the driveway before school unless I'm late and it warms up eventually. Well lately I have been late so trying to turn it on while driving I realized it mainly shorts out on high but works on low and medium, I have an auto reset fuse so it is ok. But It used to short out on all speeds and I just don't know why it is okay all of a sudden, it is always worse when it has recently rained or snowed but I don't know where te widest run, if I can re-wire myself or if I should just take it somewhere

Thanks in advance!!

Chris

W.E.G.

Wiring diagram and chase the wires. One of the least fun aspects of car-hobby by my standards, but a necessary evil.

vetteoz

iTrader: (13)

Possibly you have a short or bad connection somewhere in the Hi speed wiring circuit .
Org wire #52 in diagram that goes straight from the switch to the motor
Or the blower motor could be on the way out and drawing too much curent on Hi

For a '88 but your should be similar

Ratchet23

About where do the wires from the switch run through the fire wall and another thing is that when it does short at idle it shuts the car off sometimes if it isn't running good

ghettocruiser

iTrader: (4)

If its stumbling and not idling well, the extra load on the alternator could be enough to stuff the motor. But it could be the sign of more electrical troubles I guess. Gotta handle one thing at a time and see if fixing one thing fixes another.

The wiring, and vac hard lines, for the HVAC is all together for the most part. It runs through the firewall in a tough to reach spot. Actually, you can see it from the outside. Its kind of center and up higher on the firewall. Its been a while since Ive seen a non-modified harness, I re-worked mine. But it comes out and runs over to the blower motor and relay.

Its actually a pretty simple circuit to troubleshoot since its almost selfcontained.

I would start with the high speed circuit. Check the relay and its connector for melting. My high speed relay and its wiring gave me fits in my 87 for a while until I sort of rebooted the whole system.

J

Actually...here is a pic where the harness goes out. Its in the upper left of the pic. There is a rubber grommet you can see. Its kind of a PITA to get it out...and to get it back in.