I have had this happen a few times now and I want to put this out there to help others.
I have a 2007 G6 with about 70k miles on it. At 55k miles I noticed the car running hot and a coolant smell coming from the engine. I noticed the coolant recovery tank was low, I added coolant and as soon as the engine was started it leaked right back out.
To make a long story short I ended up replacing the thermostat and coolant recovery tank. The tank was still leaking after this was done. The problem ended up being the coolant recovery tank cap. Unlike most cars this tank has an actual 15 psi radiator cap on it. When it goes bad the coolant will just pour out the bottom of the tank when the car is running. I've had it go bad 3 times now, about every 8 months.
A mechanic at the Pontiac dealership said he's been replacing these on an average of once a week. So if you noticing your tank is leaking/low try replacing the cap. It costs about 6$ at your local parts shop.
I have a 2007 G6 with about 70k miles on it. At 55k miles I noticed the car running hot and a coolant smell coming from the engine. I noticed the coolant recovery tank was low, I added coolant and as soon as the engine was started it leaked right back out.
To make a long story short I ended up replacing the thermostat and coolant recovery tank. The tank was still leaking after this was done. The problem ended up being the coolant recovery tank cap. Unlike most cars this tank has an actual 15 psi radiator cap on it. When it goes bad the coolant will just pour out the bottom of the tank when the car is running. I've had it go bad 3 times now, about every 8 months.
A mechanic at the Pontiac dealership said he's been replacing these on an average of once a week. So if you noticing your tank is leaking/low try replacing the cap. It costs about 6$ at your local parts shop.
