Driving one day my temperature gauge began dinging at me saying my truck was overheating. I got out, felt the entrance and exit hose from my radiator and knew it was not overheating. Still I limped it home. The next morning, I went outside and turned my key on. Immediately my temperature gauge shot up to the highest bound on my gauge, so I believe my problem is a computer one.

At any rate I replaced the thermostat, sending unit, burped it, and installed a mechanical gauge to depend on while my stock gauge is wrong.

Has anyone else heard of a similar problem or had it themselves? Any ideas on how to fix it?

 

My 2000 Dodge Ram with a 5.9 V8 just started doing the same thing today. I already replaced the thermostat last summer, new intake gaskets last week. A digital thermometer shows that the upper and lower radiator hoses are not as hot as the gauge is displaying. I already bought a brand new ECT sensor with a brand new one about 6 months ago.

I hope it is just some more trapped air in the system. I guess I'll find out this evening after it cools off so I can look at it.

 

getting all the air out of the system can be a PITA with these trucks. I suggest you burp it some more , before coming to any other conclusions.

 

I thought at first that mine had just some trapped air as well as it initially started soon after I replaced my water pump. However, I burped out any air, and still haven't had any luck. In hind sight I realize that burping it shouldn't have helped me at all as my truck will say its over heating as soon as I turn the key on and it has been cooling all night. Let me know what you find out on your truck.

 

zman17
If it was only an air pocket wouldn't the temperature reading only be sporadic when the truck is hot or while it is running?

 

An air pocket can move around in the system and cause it to spike every now and then. I'm not saying that's the problem. It just needs to be eliminated as a potential problem. Then you can move on to other diagnostics.

 

If the gauge is reading hot, when the engine is stone cold, its an electrical problem. If you already replaced the sensor, and that didn't help, need to trace the wires, and find the short. (or, broken wire.....)

 

Thanks HeyYou.
Where do I need to get into to start tracing the wires?

 

My temp gauge problem ended up being the ECT sensor I installed 6-7 months ago. I installed a brand new one from NAPA and the gauge works normal again.

I did notice as another thread pointed out, the aftermarket sensors might be longer then the Mopar version, because I had the old sensor screwed in all the way and I could see where it was making contact with the intake from the bottom side of the sensor.

So if you do buy an aftermarket sensor, don't thread it in all the way.

 

I need to buy stock in whatever company makes thermostats. At the rate people on this board just swap the damned things out I know that the company will be paying out dividends for years.