i dont know what the problem is but my car has been running hot. i installed a new radiator recently and installed a perma cool 16 inch high performance electric fan. i also installed a new low temp themostat. my temperture gauge doesnt really work. i replaced the sending unit. when the car is started in says the temp is really low, but when i turn the car off and turn the key back to accesories the needle shoots up half way. is there anyway i can check the exact temperture without installing a gauge. i would like to fix my existig gauge and heard there should be a ground wire from the manifold to a ground, but i dont have this wire, and could that even be the problem. any help would help greatly thanks.

 

I think the only way to really know how hot your motor gets is to run a temperature gauge on it. The stock gauge on your dash is 35 years old and is most likely inaccurate. There is a small voltage regulator for the gauges located behind the instrument cluster. This can cause your gauges to go haywire, and may need replacement. But you still need to get an actual temperature reading to really know what you have going on there.

 

thanks

 

This is normal as long as it cools back down when engine is running. When you turn off the car the heat from the motor goes into the coolant but the water pump is not turning so no real circulation, this makes the temperature rise once you start the car coolant is pumped through the radiator cooling it down. This shows you that your cooling system is working. Dont worry.
Quig