Question about 1999 Pontiac Grand Prix

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Overheating, no coolant loss

1996 Pontiac Grand Prix | 3.1L V6 | 125,000 miles
Overheating, no coolant loss

I'll try to make this short. After having the infamous dexcool cooling system problems with the cooling system having major blackage, overheating and wifes car had major repairs for the second time (intake, heads, gaskets, sensors etc).

The last time it was done at the dealership about 8 months ago. Originally they only replaced the intake gakets for a bad leak that developed. After bringing the vehicle back 6 times (never got more than 5 miles from the delaership without the car overheating and developing blockage in the coolant system from internal junk coming loose), they finally took their time and told me they removed and cleaned the heads, power flushed, cleaned the overflow tank and replaced all sensors and the thermostat.

The car was fine until now. It overheated very badly in a short drive (less than 15 miles) and lost no coolant at all. The radiator never even got hot, yet the motor almost seized and was very hot. I had the dealer tow the vehicle in (suspecting that it would be covered with all of the work they did previously).

To my surprise, the dealer is asking for another $1600 saying it is the rear head that needs removed and that they suspect it is leaking coolant into the engine. Again. i noticed no loss of coolant at the radiator and should the dealer not have pulled both heads last time? I swear that is what they told me they did last time. Now they are saying the only pulled and worked on the front head previoulsy.

Am I wrong in assuming that both heads should have been pulled and cleaned previously? Why would they not have done that (other than the fact that the rear is hard to get to)? Am i justified and expecting that they should have?

Also, does this sound like a good diagnosis and what (if anything) should I expect the dealer to take responsibility for? The repairs are covered for 12 months, 12000 miles and it has been less than that.

Any reply would be greatly appreciated.

Posted by Anonymous on


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I have a 1996 Pontiac Firebird with the 3.8 L V6, and have had problems until I replaced the DexCool (it's never ran so good!) However relating to your problem, there was a class action lawsuit regaurding the 1996 GMC/BUICK/PONTIAC 3.1 L engine, due to DexCool destroying the engine/heads/etc. Follow the link - I do not know all of the details, but it may be worth checking out. 1996 was the first year that DexCool was used at GM.
Hope it helps.

Posted on May 14, 2009


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