89 E350 with 7.3 Liter Diesel.
On the front of the motor near the oil filler (just to the left)
there is a large threaded sensor with a harness that goes through
the firewall at the drivers feet. On mine the wires under the dash
are cut up mostly but one set goes to a light bulb.
What does this unit do? Should I attempt to get it working again
or just get rid of the wiring?

Thanks!

Larry

 

if it is two wires and comes off the timing cover, it is the tachometer harness.

 

Sounds right. Tach sensor, even if you don't have a tach. My 90 has one and it has to do with the trans shifting, and I don't have a tach.

 

Yep its an rpm sensor.

 

Thanks, never would have guessed that.
Since it's not connected to aything, I just removed the wiring.
I've already driven it 4000 miles without it connected to anything.

Larry