94 GT Temp Gauge Fluctuates

[94Stang GT]

Just bought a 94 Mustang GT with only 67000 miles. When i bought it i knew there was a minor radiator leak, but when you drove it, the leak subsided. Meanwhile...the far left temp gauge would fluctuate from hot to cold. The folks at the shop said that the leak could be controlled with stop leak until a new radiator could be replaced and it pressure checked okay. The temp gauge still fluctuated and the heater worked great and still does. Now, the temp gauge is stuck on H even when the motor is off and the engine is cool. The radiator doesn't leak much and i was thinking a thermostat replacement would fix the gauge issue. Anyone have any thoughts?

 

[Bosko5.0]

Maybe the temp sensor for the guage went/going bad.

 

[Dino Dino Bambino]

Now, the temp gauge is stuck on H even when the motor is off and the engine is cool. The radiator doesn't leak much and i was thinking a thermostat replacement would fix the gauge issue. Anyone have any thoughts?

Yeah, the gauge being stuck on H means that the circuit to the sending unit is shorted out. Either the sending unit itself is bad or the wiring to the sending unit is grounding out somewhere. Try replacing the gauge sending unit first. It's an easy, cheap fix.

 

[94Stang GT]

Temp Gauge Fluctuates

I had the radiator, cap, and thermostat replaced along with sensor. Obviously there isn't a leak anymore. The only problem is the gauge still doesn't operate correctly. The shop recommended changing the gauge.

 

[Bosko5.0]

inspect the wire that goes to the sensor see if is rubbing anything.

 

[a_k]

That happened to me, I just put in a mechanical autometer