I have 98 grand am 179K, i recent went to get an oil change the tech suggested i need a coolant flush because mines was muddy. During the flush the muddy water clogged up the thermastat and that had to be replaced. When i left the shop my engine light came on now it runs rough and sometimes shut off. What did they do to my car?!!! It was fine before then!!!
Will a coolant flush cause for you engine light to come on and sometime cut off? on 1998 Pontiac Grand Am
by carmomma in Raleigh, NC on October 05, 2011
1 answer 3 comments
ANSWER by Autoson2930 , October 06, 2011
If your coolant was muddy looking that means there was oil mixed in with the antifreeze. Most likely a gasket had ruptured and it is probably the head gasket. When they did the coolant flush they put the system under extreme vacuum and probably made the problem worse. At that mileage a coolant flush where they hook a machine up to the car should never be done. Only a drain and refill. If a faulty head gasket was the reason for the oil in the coolant and they did a flush I can guarantee the head gasket issue was made worse which will put oil and coolant directly into the cylinder where the failure happens on the head gasket.
COMMENT by carmomma , October 06, 2011
Thank you for your answer!!! Im going back on Saturday to have them hook it up to the machine to see why the engine light is on. If your answer is correct im wondering will they repair the head gasket at their expense or mines? I will keep you informed.
COMMENT by Autoson2930 , October 06, 2011
Sounds Good. If they hook it up to a scan tool it will not necessary say the head gasket is bad. There will be a misfire fault and then they will have to perform other tests ie compression tests and cylinder leak down tests to determine if it is a head gasket. I would not hold your breath on them replacing it at their cost, but hey the worst they can do is say no so why not ask.
COMMENT by carmomma , October 10, 2011
I went friday to have the car looked at and luckily it was just a bad hose that connects to one of the sensors thats in front of the car. I think he called it a vacuum sensor, im not sure but once he repaired that the car ran fine.