Temperature guage not working [Archive] - GrandAmGT.com Forum


View Full Version : Temperature guage not working

05-25-2008, 09:37 PM
Driving along and a service engine light luminates orange. Then I notice my temperature guage isnt working.

Its working in a responding to turning the key on way, If I turn the key on it moves far left then back to far right. Normally when you turn your key on it moves far right then moves to your engine temp. It will not read engine temp, it always reads far left. But its functional, but not working.

It was working before the eninge light came on.

What could this be anyone have any ideas.

Is there a sensor I should check, if so where is it.


2001 Grand Am GT V6 BTW

05-25-2008, 09:42 PM
coolant temp sensor?

05-25-2008, 10:52 PM
I wouldn't worry about that temperature gauge until the SES light is off. Is there coolant?

05-26-2008, 08:56 AM
yes there is plenty of coolant. I have another aftermarket coolant temp that is working fine, its just my indash coolant temp. Its fustrating me, Cause my engine light is on and I like to have everything working properly.

Does anyone have any ideas at all what this could be?

05-26-2008, 09:36 AM
take it to an auto parts store and have them throw the scanner on it. An ECT sensor is extremely easy to change

05-26-2008, 11:19 AM
Your t stat is probably stuck open, it will give you a SES light and the gauge will read pretty much nothing. Mine did the same thing.

05-26-2008, 11:30 AM
Scan the CEL first, that will lead you to whats wrong.:thumbs:

05-26-2008, 12:08 PM
The T stat makes sense cause my engine has been running very cool lately like 150* and around there. Im going to get a scan as soon as I can, Auto zones around here dont do the scans Ive called. But my buddy has one so Im going to get it from him after work.
I have a HP tuner but I dont know if that is able to scan for SES lites? or how

05-26-2008, 12:10 PM
Could this be the reason my gas mileage has been crap lately. From what I understand removing the T stat increases the fuel flow to run rich?

06-02-2008, 07:52 PM
Hey, I've had this problem before.

The temp gauge would read normal sometimes, then not read at all (Far left position)

Turns out my intake gasket was garbage, leaking coolant. Had it replaced ($240) parts and labor.

Most likely not the problem you are having though. That was the problem for me. After I replaced the intake gasket, gauge reads normal 100% of the time.

06-02-2008, 08:29 PM
I had the exact same issue. It was the thermostat. Not expensive at all.

06-02-2008, 08:48 PM
As stated in fourth post, vehicle apparently has an aftermarket water temp gauge, which is ostensibly reading normal operating temperature. It is also posted that coolant level is within spec. This tends to suggest against a faulty tstat. The ideal method to troubleshoot this is to use a proper scan tool and check ECT data to see if the PCM 'knows' what the temp is. Without a proper scan tool, take an actual temperature reading, eg, with an infrared thermometer, preferably at the water outlet (to see if tstat is regulating temperature properly).

If actual coolant temp is good, suspect an ECT sensor/circuit problem, failed IPC or databus fault. The temp gauge in the cluster defaults to 100 deg F when

06-02-2008, 08:50 PM
whoops, truncated the last...

The temp gauge in the cluster defaults to 100 deg F when the PCM identifies a fault with the ECT and/or circuit, OR the IPC loses communication with the PCM.

06-16-2008, 09:14 PM
Dam, that just happen to mine today, aaahhh!! how much i hate changing that dam t-stat!! this is the 4th time already!! Im getting really tired of GM making cheap crap!!