first off this is a 22re, I have never noticed this before so im assuming its not normal, when the truck is not running and the key is in the position right before starting if i leave they key in this position my temp gauge goes up?????

I have owned this truck for a long time and have never noticed this before. When I start it goes back to normal.

Im not sure if I leave it on how far it will go but in about 3 minutes it went half way up the temp gauge (farther than the truck has actually ever gotten).

So what could be causing this to happen? Im pretty slow with electronics so Im not sure if this is a pre cursor to some other type of failure. Any ideas greatly appreciated.

 

After I replaced the standard cluster in my 86 with the SR5 type with Tach, I've had issues with the temp gauge. I've had 2 that stick. The needles registers just turning on the key. I sometimes tap on the benzel to get it to read. Seems to read OK, just sticks in the place it most usually goes to when warm. The temp sensor is just a resistor that changes value as it warms up. You can actually use an Ohmmeter to test it. Or a variable resistor in it's place to test the gauge. If you have the standard cluster, these are available on Ebay at pretty cheap. Easy to change just the gauge.