Temp guage not working
 

started my 2007, 2.2l engine and after a few minutes noticed temp guage did not move, then looked to DIC and nothing for temp registered, car runs OK, not overheating, any clues, haven't started trouble shooting yet as i was just getting home from a trip. any suggestions to start looking?

many thanks for input

Beachbum

Sounds like a bad thermostat. There have been many, many threads here about this problem and these same symptoms.
Do a search here and you should be able to see numerous posts and solutions and possible warranty coverage.

thanks for the input "firemangeorge" I was wondering why it would be the thermostat if car didn't over heat if thermostat was stuck in open position wouldn't it still regsiter a temperature even if it was low. If thermo was stuck shut wouldn't it overheat? , was wondering if it wouldn't be the temp sender? any way to check one or the other without needing to buy both? note: have no codes, all wire connections tight, good contact, no blown fuses

As Fireman says....Thermostat.

You are making the assumption the thermostat went bad and CLOSED. It went bad and OPENED. As fireman says you have all the symptoms of this problem. When this occurs everyone wants it to be the easiest repair possible....the sender. But 99% of the time it's the thermostat.

But you can test it to some point. Start up your car and let it run to a point that it SHOULD be normal operating temperature. Raise the hood and check the radiator hoses. They should be cool or at least lightly warm.....thermostat stuck or, in some instances broken, in the open stage.

Again, as he suggested, you will find MAY different threads on this topic. All of them will point to your symptoms. Do a search, it is interesting reading.

Oh, and to answer you question about no temperature indicated.......and I'll be a little symplistic......that is the way the vehicle is programmed and built. You will not have other functions also.....but it isn't worth mentioning those right now.

Snoopy's quote at the end says it all. I bow to your superior knowledge, You are correct, it looks easier to change the sender than the thermo. to quote "back in the day" it was a lot easier to troubleshoot these things and change the parts too. THanks again to this forum, I've saved a lot of money and hassle. And my wife can't understand why I am always on this site, silly girl

I can't see why the thermostat would be where you start....
If the thermostat is stuck inclosed position, then after a few minutes of driving, you would boil over.....
If it was stuck open, then it would take forever to warm up, and in this cold weather, the heater would not feel as hot as usual.
Check for those symptoms.....
However, no data change at the DIC and no movement on the gauge says electrical issue to me.....
Check your wiring to the sending unit.
If the wiring is fine, I would replace it.

But, as stated above......you mentioned running a few minutes......make sure the engine is warm, and the heater is blowing warm air....then check to see if you have any readings...if not....its electrical..(ie..sending unit.)

Many folks have reported the same symptoms as the OP and as Snoopy said , it is usually the thermostat. Most times it is the rubber gasket/Oring that breaks loose and wedges the thermostat open.
Why the --- reading on the DIC? Because the car's computer senses that the coolant is not heating up fast enough. Therefore the computer sends the "no reading" to the DIC. Apparently, it's just the way GM programmed the computer to not give a reading when you have a slow warm up.
The car can still warm up enough to produce some warmth from the heater. Just won't be fast enough to satisfy the computers algorithms.
I still put my money on it being a bad thermostat.

I would normally lean the same way as you on this kind of question but these cars seem to be very different in regards to normal tale tale signs. Like for example having the transmission go into a hard shift scenerio for things like the powersteering go out or the cam sensor going out. It looks like GM has came up with ways to get the average consumer to freak out and take the car into the shop sooner then later.

well, at least living in FL does have a benefit, I don't need the car heatermuch if at all. so I can replace one item, check and then replace4 the other if needed.

Thanks to all for your input, I just love this site.

Beachbum 1

It's the thermostat. As Firemangeorge said, it's the way it works - and you will likely find that the A/C is inoperable at the same time as the CEL is lit (the CEL will NOT come on every time, as it is dependant on specific circumstances - but will give a P0128 when lit).

Usage of the SEARCH facility (- hint hint ;-) at the top of the page) would have quickly found this great writeup on replacing the thermostat https://www.chevyhhr.net/forums/how-tutorial-library-21/how-save-%24350-00-thermostat-replacement-2-4l-p0128-24493/

and https://www.chevyhhr.net/forums/show...ighlight=p0128 is interesting reading as well