Wierd temp gauge behavior 2005 Silverado 5,3 V8

[Jens Granath]

Hello from nothern sweden, 

I'm a fairly new owner of a 2005 Chevrolet Silverado 5,3 liter V8. A couple of months ago I noticed that my temp gauge would'nt rise at all. I changed the temp sensor and after that it behaved as expected. Rising to just shy of 210 degrees (98 celcius). Yesterday the needle suddently dropped to the bottom after reaching normal operating temperature. I have driven it several times after that: when I turn the engine off and turn on the ignition, the needle will often (not always) indicate the expected temp when the engine is warm. Sometimes it stays att the bottom of the scale. Other times I can start the veichle and drive for a couple of minutes with the gauge showing the expected temp just for it to die suddently.

 

Am I the victim of a bad replecement temp sensor or should I worry about someting else? 

 

Probaly unrelated: the night before I first noticed the problem I had tried to reconnect some extra lights that the previous owner had disconnected, and I attached a ground cable in the engine room.

 

(I have tried to disconnect the battery for more than an hour, the problem still returns). 

 

Thanks in advance. 

[shakenfake]

It sounds like it could be a bad stepper motor in the gauge cluster causing the needle to not operate properly

[dna9656]

I agree with Evan above, but it could also be in the circuit connecting the sensor to the gauge, or a bad ground Check your grounds in that circuit, make sure they are clean and tight.

Replacing a stepper motor is pretty easy, you pull the instrument panel, turn it over there may or may not be a rear cover (I have an 06 Avalanche but I don't remember) anyway the stepper motors are about the size of a US Half Dollar coin you can get them on Amazon or E bay they are soldered in I believe; If you don't know how to solder on a circuit board you might ask your friends for some help This procedure is most likely on the forum here or other forums if I'm wrong on how to do this. My instrument cluster had many issues, no lighting, stepper motors didn't work; I replaced the stepper motors and LEDs but I ended up buying a used one off the internet, I was trying to get the Escalade EXT panel because it had a transmission (lower left corner) temp gauge but my source didn't have one on hand at the time.

Good Luck!

[Jens Granath]

Thank you both! I talked to a friend last night and he thought that my fiddling with the wires to the extra light might have something to do with it, that I might have disturbed the connection to the sensor in some way, causing a bad ground. I'll look closely at that first, and the secondly at the gauge itself. 

[Jens Granath]

Update: I removed the contact of the temp sensor, turned the cable a few times (looked twisted): now the problem has yet to show itself again. Temp readings are nominal  

 

Hope it stays this way!