Which temp sensor controls ECM

[Thor]

I plugged in a scan tool to my 94 6.5 diesel, its shows engine coolant temp at 304 degrees cold. Which temp sensor sends temp to computer, the one one the top right of engine? or the one in the front left block?? Thanks

[joed]

The top right one, near the intake manifold.

Sounds like you may have a bad sensor or an open in the circuit.

Joe.

[DmaxMaverick]

I would suspect a failed sender (usual suspect), or dead short.

Open should indicate -40°ish. Test the connector at the sender for a short to ground if it repeats with a new sender.

[Robyn]

Top one near the water outlet.

Yessssss, the thing has likely failed.

As Maverick said, unplug it and the scanner should read -40 ish

Try unplugging, then scan it, and if you get the -40 reading or somewhere close, just replace the sensor and life should be good again.


Missy