65coupe88hatch

my temp gauge has never worked since i bought this car...so i thought the thermostat was bad changed it, changed the temp sensor, coolant temp sensor, didnt do anything. now tonight i started the car about to test the brakes and the idle surged and stalled the car. when i started it the gauge jumped but didnt move again. now that was the first time i saw the gauge move, what can i do to test the gauge working. or what can the causes be? what wire directly goes to that gauge, like the temp sensor? please any help would be awesome

fourfivefour

The coolant temp sending unit has a red/white wire going to it. (Not to be confused with the engine coolant temp sensor) Do not ground or apply power to this wire you will damage the IVR.
Disconnect the red/white wire and connect a test light between it and ground, turn the ignition to run and the best light should be blinking.
If the light does not blink and stays light steady the instrument voltage regulator(IVR) needs to be replaced.
If the light fails to light or blink, check for broken red/white wire,open IVR, bad gauge, or bad printed circuit board on the back of instrument cluster.

If yourother gaugesare working properly I would suspect, wiring, gauge, or circuit board. Not the IVR.
The IVR is held on with a screw on the back of the cluster.

65coupe88hatch

thanks, ill check that out tomorrow