Can this be the over heating cause?

AZ-Z71 · August 19, 2003

I was in and under the truck in the area of the temp sensor other day while I was changing my half shaft. As I was wiping the grease off that got slung around I noticed this sensor with a wire and thought it may be the temp sensor. As I looked to the right where the header comes around the first spark plug I noticed that the bolt head has been sheared off clear down to the block. So now I'm wondering that when the truck is standing still in line or park with the engine idling if maybe excess heat is escaping from the header right next to the sensor and therefore the giving false readings. If you rev it up maybe there is enough air flow in the engine compartment or the action of reving pushes/pulls the heat away from sensor to eventually come down.

Could this be the problem and the truck not actually overheating? On the temp guage the needle jumps up pretty choppy like two lines at a time holds then a few more. Never seems to make it to the red but pretty close. After reving it takes a few seconds or so to come back down, usually pretty smooth but fast.

I've changed just about everything except the sensor and the fan clutch. I'm not convienced it is the clutch since I can't spin it freely either hot or cold.

MountaineerTom · August 20, 2003

good find. That's a very good possibility.

Do you have a V-6 of V-8?

Both have them on the driver's side. The V-6 appears to be back by the steering shaft and the V-8's right behind that little remote battery jumping terminal that has a red plastic cover and the power steering fluid reservior.

You could try running the engine and see if you feel any heat/air flowing from that area. It may be hard though witht he fan blowing air also.

Be careful and watch where you put your body parts.