Temp gauge ???

Hey there, should the gauge needle be about half when 231 v6 engine is warm, or full pegged reflects a hot running engine??? When engine is about 160 gauge is maxed compared to my back up mech gauge! New gauge, if I put gauge wire right to ground it pegs full... Gauge slowly gets to hot with engine running but why all the why to hot??? Sensor is 283 cold, 56ohm middle and o ohm when hot! Seems to me sensor and gauge working correctly.. Just why holding at pegged hot?? Thanks j

 

Sounds like a bad sending unit for the stock gauge or a shorted wire to the gauge.. How is your gas gauge working, obvious signs like the radiator spewing antifreeze?

 

Your gauge and sender have to be a matched pair for resistance. For the stock SW gauge the sender resistance has to be high resis cold, 73 warm, 36 about 1/4, 13 about 3/4, and 9 ohms hot (or pegged).

 

After confirming values for the sender: disconnect the wire, put your digital ohm meter on it and then start the engine. As it warms you should be able to see the resistance go from high to low. For mine it went from about 170 ohms cold to about 40 ohms steady when normal hot. That will isolate whether the sender is the source of the problem.

Then check the wire - on mine it was blue with a yellow tracer,16 awg. I found damage, heat mostly, so replaced it with a 14 awg blue wire all the way to the sender, also replacing both male and female Packard connectors at the firewall as they were very corroded.

While disconnected, I checked resistance at the gauge, nothing. So I figured it was dead and replaced it as well. I now get a reading albeit not accurate. I figure I need to now calibrate it. I also replaced the fuel gauge at the same time as it was not working and appeared the CVR was dead as it didn't have a voltage output. Fuel gauge is working fine now as it went ahead and retired it's sending wire (white, now 14 awg) and also grounded it well, both sender and gauge cluster.

Hope this helps.

Tim