So I have a 2001 Dodge Dakota with a 4.7L engine and its been acting strange lately. While driving the temperature gauge suddenly jumps to the high side and the CHECK GAUGES light comes on.It is sporadic and I am sure the engine isn't actually over heating. Other times the gauge will slowly decrease to the point where the computer thinks its -40°F and the engine starts to run rough. The temp. sensor has been replaced twice and I have had the wires checked between the PCM and the sensor by a mechanic and he found no problems. At this point I am left scratching my head on what to do next except replace the PCM. If anybody could chime who has had a similar problem or possible solution I would greatly appreciate it.

- Link to a video of the gauge acting up while parked.

 

That's a bad sensor, a wiring issue, bad PCM, or cluster...... Try plugging in with a scanner that will read data, and see what the PCM thinks engine temp is. If the PCM is seeing the right values, then the cluster becomes the chief suspect.

 

PCM readings are all over the place for temperature. When the truck thinks its over heating it reads 390°F and when it bottoms out it reads -40°F. The only thing I can imagine it is now is the PCM but, I honestly know very little about them or how they work. I've looked into buying a replacement but it seems you can't buy them new. The only places that sell them are suspect remanufacturer websites and junkyards.

 

PCM just interprets a signal from the sensor. You have a bad sensor, or, a problem with the wiring.

 

Ok so this thread is beyond dead but I wanted to say that the temp sensor was faulty from the manufacturer and replacing it again is what solved the issue. Just wanted to add some closure to this thread in case someone stumbles upon it with a similar issue.