1986 Iroc with 305 carb motor. Single fan. The fan will run continuously unless I disconnect the battery or unplug the fan pig tail. I have checked the following: temp sensor near the thermostat. Temp sensor near the plugs on the passenger side, ac clutch fan relay, and the fan relay located near the radiator. Is there anything else to check? When I unplug all of the items above the fan still continues to run. I have been told it could be a bad fan that is grounded out or the ecm. Any help will be much appreciated.

 

Unplug the cylinder head temp switch

 

If that’s the one in between the plugs on passenger side I already did and it didn’t help

 

How many "improvements" have been made to the wiring?

 

good question, have you pulled the relay. The contacts could be stuck as . But pulling the relay indicates the wiring is hacked

 

Have not had any improvements done. When I disconnect the relay fan still runs. I pulled the plug just now from the back of the fan and checked for juice with the switch off. I have juice on one side of the plug when the switch is off. I’m thinking the problem could be between my pig-tail that goes into the fan and the relay?

 

Orange juice?

 

Im using a test light so one side lights up one side don’t with the switch off

 

The fan relay is located on the firewall near the brake booster and master cylinder. Unplug it. Fan go off? should. The relay you unplugged is for the throttle kicker.

 

And you know this ... how???

Impossible without wiring "improvements", assuming (yeah I know) you unplugged the right relay.

Not sure what this means. If it means anything.

No. Not least because, there's no "pigtail". Just a wiring harness. Which sounds like somebody somewhere somewhen for somewhy, decided to short the blk/red wire between the relay and the fan motor, to the red wire feeding hard battery to the relay. Hard to say who when where or why; because, you know, HUMANS. I can only hope that the next planet they assign me to, that the species on it that considers itself supposedly "dominant", is more logical and rational and intelligent than THESE stuuuuupid things.

Instead of telling us that we're all full of crap, (not that we necessarily aren't; just, our cars work, and yours doesn't, and when ours don't, we know what to look for to fix them) check your wiring carefully for "improvements". If I were the betting kind, which I'm not, I'd bet you'll find some.

 

This made my day!