2004 pontiac temperature gauge just stopped working.
Drove car this morning it was working.
Shut off the car, went it store, started the car and noticed no temp gauge and the cooling fans were blowing.
I do have a lower intake manifold leak....not too severe, that I'm in the process of fixing.
What would cause gauge to stop working, causing the cooling fans to kick on?
Country: United States
Make: Pontiac
Model: Grand Prix GTP
Year: 2004
Engine: 3.8 supercharged
Already Tried:
Currently using 180 degree T-stat. That was installed 3 months ago. Checked HVAC fuse, that is ok.
Submitted: 2 days and 16 hours ago.
Category: Pontiac
Value: $18
Status: CLOSED
Expert: George H replied2 days and 16 hours ago.
Hello I will help you with your question,
Is your coolant full?
If the coolant drops below the tip of the coolant sensor then it will read cold and the engine computer which "knows" it should read normal will flag this as a problem, turn on the fans as it cannot be sure of the temperature and turn on the check engine light.
Let me know if this is the case
Thank you
Customer replied2 days and 16 hours ago.
Yes, coolant recovery tank is full and radiator is full... close to the neck.
Expert: George H replied2 days and 16 hours ago.
OK, check the coolant sensor connection and the sensor resistance if you have an ohmeter. The gauges do go bad on these years but usually the computer does not turn on the check engine light or turn on the fans if that happens.
Let me know how I can help you with this
Thanks
Customer replied2 days and 16 hours ago.
I'll check the connection.
I don't have an ohmeter.
The check engine light is not on....only the fans.
Expert: George H replied2 days and 15 hours ago.
Sorry I don't know where I got that... You can disconnect the sensor and bridge the connector with a paperclip (don't let it touch the engine metal!) and see if the gauge goes full hot. If it does the problem is in the sensor.
Let me know how I can help
THank you
Customer replied2 days and 15 hours ago.
ok, I'll try that.
If I take it only short distances, it is still driveable?
Expert: George H replied2 days and 15 hours ago.
As long as the coolant is full, the fans are running and the engine does not seem like it is overheating it is safe to drive. YOu can run the heater and if it starts putting out super hot air or goes dead cold you need to stop the engine
Please let me know how I can help
Thank you
Customer replied2 days and 15 hours ago.
with the clip bridged, should I be able to get a reading with the car off?
Expert: George H replied2 days and 15 hours ago.
YOu will need to turn the key on to see the gauge move and wait for a minute to see if there is any action.
Please let me know what questions you have
Thanks
Customer replied2 days and 15 hours ago.
no movement with the gauge.
Expert: George H replied2 days and 15 hours ago.
Sounds like the gauge died but you do need to have the codes pulled from the computer. An autoparts store will do this at no cost but I think you know this. If the code is a cooling system code you still need to look further, if you have a scanner that will show data look to see what engine temp is displayed.
Let me know what you find with this so I can help
Thank you
Customer replied2 days and 15 hours ago.
Ok, I'll check it out.
Expert: George H replied2 days and 15 hours ago.
Please let me know what you find, any code you may get and what I can do to help
Thanks
Customer replied2 days and 12 hours ago.
Ok...
When I reconnected the coolant temp sensor, the check engine light came on and stayed on until I got it scanned.
The code that came up was "coolant temp sensor" and the reading for the coolant was, "cool."
Is it safe to say that it's the coolant temp sensor causing this problem?
Expert: George H replied2 days and 12 hours ago.
If you clear the code and run it through a heating cycle, let it cool down and run it through one more cycle on the third cold start the code will reset if it is a valid code. The code may have set due to the sensor being unplugged with the key on.
Did you get the code number?
Were you able to see the data for the coolant temperature when the code was read?
Customer replied2 days and 12 hours ago.
I didn't get the code number, but I did see it say, coolant temp sensor.
I just asked what the scanner said about the coolant temp. and he said that it was reading as "cool."
I'm going back tomorrow to pick up a temp sensor.
I'll get you the code number tomorrow.
Thanks for your help.
Expert: George H replied2 days and 12 hours ago.
If the engine temp shows cool when it is hot you problem is not in the gauge. While you are there turn the key off, disconnect the sensor, put the paperclip in and start the engine. If it now shows a code and shows hot on the engine temp on the scanner then you need a sensor. If it still shows cold then you have a problem in the wiring between the sensor connector and the computer.
Please let me know what you find when you get a chance to check
Thanks
Customer replied2 days and 12 hours ago.
Ok, I'll check for all of that tomorrow.
Expert: George H replied2 days and 12 hours ago.
I will watch for your post tomorrow. No need to reply til then.
Thanks
Customer replied1 days and 17 hours ago.
Hi,
sorry for the delay, my pc had a problem.
As for the grand prix, I started the car this morning and the gauge was working properly and the fans were off.
Drove around today, shut the car off, started the car up and the gauge was working properly and fans remained off.
Did not go over to have the car scanned.
Expert: George H replied1 days and 17 hours ago.
Sounds like the connection may have been restored with your testing. At least you know what to do here when it quits again.
Please let me know if you have questions about this
Thank you
Customer replied1 days and 17 hours ago.
Alright, thanks for your help.
