Is there any way to test the gauge cluster ? The only time I noticed the gauge work was when the engine ran hot. . ..Oh yeah one more question . Which sensor is for the gauge , There is one that is on the thermostat housing and one mounted in the in intake manifold ..

Any help ?

 

which engine? the 22re is located right on the top where the upper radiator hose meets the block. you can test the gauge by grounding the wire, if the gauge is working it should read all the way hot when you turn the truck to accessory (but search for the specifics i just know the jest of it) mine dies the same crap. Just bought a aftermarket gauge.

 

Actually for the 22RE, the sender on the thermostat is typically one or more of the following:
1. A/C high temp cutout
2. Auto trans. computer coolant temp
3. Extra temp. sender for 22RE-turbo

Gauge sender is down in the intake manifold near #3 cyl. as I recall.

The Factory Service Manual has the gauge and sender testing procedures.