[Charlie]

Hello all! Short time listener, first time caller. I am here today seeking help for my 2007 G6 GT, which I have affectionately named the "Hydra:" For when one mechanical problem is solved, two more take its place.

For a while now, my heater hasn't been working well/at all until the engine reached temperatures over 225°. Even then, it didn't produce much heat. I had read some posts on here, and added more coolant (prediluted) to the cold fill line. (Note, it had been low a few times in the past few weeks) I then took it for a drive, and it maintained slightly lower than normal operating temperature the whole drive. I parked, and let it set for the night. When I went outside this morning, there was a massive puddle of coolant underneath the car. It is apparent that there is a leak, but I have no idea where to look for it. What do you fellows recommend I do?

Symptoms: Overheating, large coolant leak, nonfunctional heater, and lower MPG.

Action taken: I do not have access to many tools, or even a jack, so I have not done much to it. Oil pressure sensor has been replaced recently, if that's related at all. Coolant has been added to the cold fill line before starting the car at all. Under the hood, my untrained eyes couldn't see anything leaks (looking from the top). Coolant cap is on tight, and oil level is normal.

Any help is appreciated, and I will try and provide as much additional information as I can.

 

[INDY86]

The V6 engine has a 2 coolant crossover gaskets that are prone to leak . Use the search tool and look for crossover gasket leak for posted information about this .Good luck .

 

[bear52]

Hello all! Short time listener, first time caller. I am here today seeking help for my 2007 G6 GT, which I have affectionately named the "Hydra:" For when one mechanical problem is solved, two more take its place.

For a while now, my heater hasn't been working well/at all until the engine reached temperatures over 225°. Even then, it didn't produce much heat. I had read some posts on here, and added more coolant (prediluted) to the cold fill line. (Note, it had been low a few times in the past few weeks) I then took it for a drive, and it maintained slightly lower than normal operating temperature the whole drive. I parked, and let it set for the night. When I went outside this morning, there was a massive puddle of coolant underneath the car. It is apparent that there is a leak, but I have no idea where to look for it. What do you fellows recommend I do?

Symptoms: Overheating, large coolant leak, nonfunctional heater, and lower MPG.

Action taken: I do not have access to many tools, or even a jack, so I have not done much to it. Oil pressure sensor has been replaced recently, if that's related at all. Coolant has been added to the cold fill line before starting the car at all. Under the hood, my untrained eyes couldn't see anything leaks (looking from the top). Coolant cap is on tight, and oil level is normal.

Any help is appreciated, and I will try and provide as much additional information as I can.

If it obvious it's not a hose/resevoir "T", and all the normal stuff, I'd bet on the crossover gaskets also. It's hard to see when these thing fail other than the puddle on the floor. I did this job. Not a bad job. Just have to take a lot of stuff off, and put it all back. Good Luck and keep us advised.

 

[Charlie]

If it obvious it's not a hose/resevoir "T", and all the normal stuff, I'd bet on the crossover gaskets also. It's hard to see when these thing fail other than the puddle on the floor. I did this job. Not a bad job. Just have to take a lot of stuff off, and put it all back. Good Luck and keep us advised.

Thanks for the reply (both of you), I have a small update to post. For some reason, the coolant is no longer leaking (for now, anyway). I filled it back up, ran it for a while and the drip slowed and then stopped. I will be closely monitoring fluid and temperature levels, and will keep you posted if anything changes.

 

[bear52]

Thanks for the reply (both of you), I have a small update to post. For some reason, the coolant is no longer leaking (for now, anyway). I filled it back up, ran it for a while and the drip slowed and then stopped. I will be closely monitoring fluid and temperature levels, and will keep you posted if anything changes.

Charlie,

Your symptoms are the same as mine were. Some days, there was a big puddle on the garage floor, some days, nothing. I originally thought maybe the water pump, so I changed it. Same problem. It's difficult to see under there where the leak is coming from, so my only other option was to tear it apart and change the crossover gaskets. I have attached a picture of my defective one.. I hope it comes out O.K. As you'll see, it was actually the rubber ring "INSIDE" the gasket. My thought is that this was here since the day I purchased the car...I mean...how could it be anything else ??? And, thinking back, I think this car DID leak from day one. Good luck and keep us advised.

 

[Charlie]

Charlie,

Your symptoms are the same as mine were. Some days, there was a big puddle on the garage floor, some days, nothing. I originally thought maybe the water pump, so I changed it. Same problem. It's difficult to see under there where the leak is coming from, so my only other option was to tear it apart and change the crossover gaskets. I have attached a picture of my defective one.. I hope it comes out O.K. As you'll see, it was actually the rubber ring "INSIDE" the gasket. My thought is that this was here since the day I purchased the car...I mean...how could it be anything else ??? And, thinking back, I think this car DID leak from day one. Good luck and keep us advised. View attachment 18430

Thanks again, I will be taking it to a shop as soon as money allows. Will update as more information comes along.

 

[Pontiac man Pa]

Hello all! Short time listener, first time caller. I am here today seeking help for my 2007 G6 GT, which I have affectionately named the "Hydra:" For when one mechanical problem is solved, two more take its place.

For a while now, my heater hasn't been working well/at all until the engine reached temperatures over 225°. Even then, it didn't produce much heat. I had read some posts on here, and added more coolant (prediluted) to the cold fill line. (Note, it had been low a few times in the past few weeks) I then took it for a drive, and it maintained slightly lower than normal operating temperature the whole drive. I parked, and let it set for the night. When I went outside this morning, there was a massive puddle of coolant underneath the car. It is apparent that there is a leak, but I have no idea where to look for it. What do you fellows recommend I do?

Symptoms: Overheating, large coolant leak, nonfunctional heater, and lower MPG.

Action taken: I do not have access to many tools, or even a jack, so I have not done much to it. Oil pressure sensor has been replaced recently, if that's related at all. Coolant has been added to the cold fill line before starting the car at all. Under the hood, my untrained eyes couldn't see anything leaks (looking from the top). Coolant cap is on tight, and oil level is normal.

Any help is appreciated, and I will try and provide as much additional information as I can.

Bad thermostat