Got a question. My temp guage on my 87 Z has given up. It shows a constant less-than-zero setting. When I bought the car, the origional owne had set up one fan to run constantly, now, niether one comes on, and I'm unsure if the two are related or has a relay gone bad?

 

They're not related. There's no wiring shared between the gauge and the fan system.

 

umm the censor on the block/head may have came off if some one was in the engine bay. happened almost everytime i changed theoil in my 84 camaro. as for the fan thats suppose to come on at all times as the po inteaded...its been hot wire and unless its been undone im putting money on the motor burned out. as for the 2nd fan? im guessing burned motor or bad relay.

 

Check your temp gauge by grounding out the wire that goes to the sensor, located on drivers side head, grounding it out should go all the way hot (I believe) and then put 12 volts to it and it will go the other way (I believe). I could have that backwards but either way you get the point. This will tell you if the gauge or wiring is bad. If nothing changes when you do this, remove the gauge pod and test the gauge again. If it works that way and not from where the wire plugs to the sensor, your wire is shorted out or broken. Easiest to run new wire. Most the time the gauge is not bad. If the gauge did work when you tested where the wire meets the sensor then your sensor is either the wrong one or bad. Make sure you get a temperature sensor, not a switch. The one that autometer sells seems to read the most accurate. The difference between the switch and sensor is that the switch is just an on off circuit basically, used for dummy lights and fans. Which brings me to the fan. There is a temperature switch located usually in the intake somewhere (TPI in the front) which has two wires going to it. This switch turns the fan on and off. I'm not sure how to test that switch, I would just replace it and my thermostat. Also, if you don't have a thermostat the fan may never run because the engine doesn't warm up properly. If replacing those doesn't work you can replace the fan motor or the entire fan.

 

Sounds like a good idea, but I'll have to wait till it thaws out. Got 4 inches of snow and an inch of ice in the yard, and too cold to spin wrenchs under the carport. Gotta love this global warming...

 

Where exactly is the fan relay located, on the firewall or down by the radiator?