I changed my vp44 injector pump about a month ago. Several days after that, my temp gauge will warm up to ~190 as usual, then begin to start swinging from 190 down to 140 (the minimum) and every where in between. The gauge never goes over the normal temps that it usually runs at (190). I am not connecting this to swapping out the pump, but I guess I could have bumped a wire. Does this sound like the temp sensor malfunctioning? Is this common?

Are the temp sensors available for Cummins? Anyone have a part number and estimated cost? I bought an oil pressure sensor from Cummins about 6 months ago and the price was about 1/4 of what the Dodge dealer wanted.

 

i would check your connection and if that isnt it start to look at your thermostat

 

FWIW, these trucks usually never run a constant temp, and will be more pronounced in cold weather. My 24v gauge never swings like that that I have noticed, but my 12v sure does. It will go from 190 down to 160 and back up again, and that was like that for an 8 hour drive in warm weather. I haven't paid attention to it since it has gotten colder. I wouldn't be overly worried myself, as long as it doesn't over heat and you have warm air in the cab.