Engine/Transmission (1994 - 1998) LOW engine temp

[MMiller]

Hey 2nd genners.



My brother has a 94 2500 4X4 5 spd 3. 55 etc. Been running ok latley(bought it used from a guy that didn't enjoy owning a diesel ) had a lot of glitches.



The other day he started and ran the truck and it is getting no engine temp. Yes it is getting colder around here but not cold enough to be blocking the radiator yet. He blocked off the rad and still nothing then very little heat and the top radiator hose was not warm. He changed the stat. Got his in cab heat back, and a warm radiator hose, but still no engine temp on the gauge. Has been driving it( we think it is with the gauge/sensor) and sometimes the gauge works and sometimes not.



He unhooked the wire and grounded it, went to high temp, and then with no ground it goes to cold.



It sounds like maybe a bad ground or bad wire. Any body else run into this yet? Nothing else is acting up, so I don't think there is a block ground problem, and is seems like the gauge is working. Maybe the sender is not getting grounded to the block?



Sorry for the long post. Hopefully you second genners can help us out.



Michael

 

[Deezul1]

When my 97 did that the gauge wouldnt even move and thats in Texas and it was a stuck open stat. Even with a new Cummins stat it hasnt got much past 150 degrees when its been 50 deg outside but thats running around town. Its time to remove the fan for winter running.

 

[illflem]

Where did he unplug the wire?

I've run into some where the connection at the sender has been partially unplugged and read -0-.

 

[Howard Durand]

As Bill says, it could just be a bad connection.

If not, he could test the sensor with an ohmmeter. If it is cold, around 50 deg. F, it should read between 18,000 and 22,000 ohms. If warmer, it would read less. If colder, it will read more.



By the way, it has the same specs as the ones used for intake air and for auto transmission temperature.