Heat gauge

[RobL]

I’m sure this is posted on here somewhere but I couldn’t find it.

92 sierra. 4.3L. Changed both temperature sensors but now when the engine gets a little bit warm the gauge immediately spikes.

Bad ground? Wrong sensor?

Any ideas?

Thanks

 

[PlayingWithTBI]

Changed both temperature sensors but now when the engine gets a little bit warm the gauge immediately spikes.

Bad ground? Wrong sensor?

When your CTS reads high resistance the gauge should read colder, when it sees low resistance the gauge will read hot. Sounds like your sensor wire may be shorting out somewhere between the sensor and the cluster.

 

[Supercharged111]

Or there could be an actual overheating problem? We didn't get much background.

 

[PlayingWithTBI]

Or there could be an actual overheating problem?

That's a possibility too. A scanner will tell if both sensors are seeing the same thing. An Ohm meter will too.

 

[PlayingWithTBI]

ANNND, thinking about it, when the gauge pegs hot, disconnect the wire going to the sender (between cyls 1&3) to see if it goes to cold.

 

[1997]

You can check using a thermal temp gun. They are cheap and easy to use.

 

[RobL]

Or there could be an actual overheating problem? We didn't get much background.

No it’s not overheating. New thermostat and water pump.

 

[Supercharged111]

No it’s not overheating. New thermostat and water pump.

Doesn't guarantee it's not overheating without some objective proof that it's not.

 

[packer0440]

This was causing me a lot of trouble for a while. Gauge would read higher than it should. Tried changing the temp sender. Then it would read overheating when temps were normal. Put the original one back on, then cleaned up the body ground going to the battery, then it started reading perfectly.

 

[east302]

No it’s not overheating. New thermostat and water pump.

Try bleeding the system again?