Oldsmobile/Buick Repair: 88 buick scylark 6cyl., temperature gage, coolant level

Question
temperature gage reads intermittent.Replaced cooling fan relay, no cure.What to do?

Answer
Hello Jerry,
The temperature gage is supplied voltage from a fuse, and a temp sender completes the circuit to ground, depending on the temp of the coolant.
Several things will make it work intermittently.\
One is a loose fuse, wire connection at the gage, or at the sender.
Another is a bad sender or gage.
And another thing is if the coolant is low, and not touching the sender.

The sender should only have one wire connected to it. When you remove that wire, with the ignition switch on, the gage should go all the way to one end.
Then hold that wire against a good ground, and the gage should peg out in the other direction.

If it does both of those, the gage and wires are probably good, and the sender, or coolant level is probably the problem.

If the gage doesn't act like described, then the gage is bad, or the wire or fuse is loose.

Van