Temp gauge problems?

[Noah96]

Hello all my temp gauge doesnt work. I ran a new section of wire that replaced several bare spots and put a new connector on it and took steel wool to the sensor to clean it. Let it idle for 10 mins and needle barely budged(This wasn't a cold start was running earlier). I grounded the wire to the alternator and it laid over to the left of cold when it was grounded? Any thoughts?

[dmjlambert]

I've got my right mixed up with my left here. When you ground the wire, are you putting it on the case of the alternator someplace where there is bare metal or on a terminal of the alternator? When you ground the wire to the body of the truck or engine, and the key is in the on position, the gauge should peg hot, which is all the way to the right. Is that what you see?

[Noah96]

I touch it to the bare metal on the case and key is in the on position, and it lays over on C off the gauge

[dmjlambert]

That is interesting, puzzles me. I think perhaps somebody more knowledgable than me may chime in and tell us what could possibly cause that.

[Noah96]

Just talked to a mechanic and said since I had heat from blowing that I could change my thermostat out and start there since it could be the culprit.

[TBONE1964]

Do an ohm test on your temp sender. You should at cold engine get around 750 to 800 ohms of resistance, possible more

If the engine is lets say around 180 degrees, then you should see around 200 ohms give or take.

If say the coolant is 140 *F, then

Check that number and see what it is and let me know.

Take the resistor from the temp gauge and ohm across, should be in the 85-95 ohm range.

Now with that said, does the needle move at all? Is there power on the gauge? Does the fuel gauge work as it should? Fuel and temp gauge share power. If neither work, then look for a power issue on the #3 wire of the cluster connector. It will be pink, if factory.

I can help you diagnose any issue with this.

Take care,
Tom

[Noah96]

Thanks for the input everyone ended up checking the thermostat it wasnt there! went and picked one up at the parts store and gauge works great now.

[REDROCKER652002]

Originally Posted by Noah96

Thanks for the input everyone ended up checking the thermostat it wasnt there! went and picked one up at the parts store and gauge works great now.

Is your sending unit on the thermostat housing? I am having an issue with my temp gauge, a post will be forthcoming with some ohm readings, but the sending unit is on the left side of the block not in the thermostat housing.

Thanks

RR