I’ve got a 1994 Camaro and I just put in some long tubes and while I was putting them in I broke the old temperature sensor (for the gauge), I bought a new one and installed it. After I installed it and got everything done I realized that after starting the car and running it for a couple minutes, the gauge maxes out above 260 (although the actual coolant temp is much lower), I’ve bled the coolant system and checked for any spots where the wire could’ve been pinched and grounded out on the header. I can’t figure this out so any suggestions to resolve this would be greatly appreciated. Thanks in advance.

 

Did you thoroughly bleed the air out of the cooling system? If you have an air bubble in the back of the head it can cause a high reading. See (refill) bleed procedure in this reference:

4th Gen LT1 F-body Tech Articles

Test the sensor, and the wiring. Shoebox has a procedure. You want 12 volts on the wire, measured to a good ground, and you need to measure the sensor ohms vs. temperature and compare the readings to the chart.

An open in the single wire would be infinite resistance, corresponding to a very low temperature.

4th Gen LT1 F-body Tech Articles