Temp gauge malfunction. Help needed.

[Al]

I just started up this Bronco II after getting it 2 years ago.
The temp guage does not move at all even after 10 miles of driving. Other gauges work normally.Temp seems ok so I need to find out why the gauge doesn't indicate anything.
I've never had to troubleshoot a gauge. How do I tell if its the sender, the gauge or something else?

Thanks, Steve

[Nobody]

Unplug the wire from the temp sending unit and ground the wire. That should cause the guage to peg. If it doesn't peg then there is a break in the wire or the guage is bad.

[Al]

Thanks nobody! Al.

[CraigK]

I had the same thing. I replaced the sending unit that screws in at the front/top of the motor. Wasn't very expensive, and works fine now.

CraigK

[slamball]

Same thing was happening to me a while ago. After I over-heated it it has worked ever since.

[CBlue]

My sending unit worked but the gauge on dash would randomly show major overheating, yet the radiator wasn't boiling excessive. I was panicking since I just put in a now longblock a year earlier.

I had a radiator mechanic use an Infer-red gun, measure all points of cooling system. He came back with the famous... cant get it to overheat.. 5 minutes from leaving shop, it was showing overheated..eventhough i just had the mech change out the sensor on engine. He tried to blame it on the lack of a substantial fan shroud. My truck has the stock blade protector only. (no ac or auto trans).

I added a fancy (chrome) radiator cap that had a temp guage, and a mechnical temp guage system. As i discovered, It's rare that I even hit 195f setting for themostat to open.

Without auto transmision or AC the cooling loads for a 2.9 is minimal. General air flow and minor flow through the thermostat pinhole keeps the engine cooled. Ran all summer +100 without a problem.

Good luck