Why is my car overheating?

Hi Nina, check to see if the thermostat is operating correctly and if the coolant level is low.

Possible Northstar head bolt failure.

My thoughts exactly! Before spending any money on this vehicle have the coolant tested for exhaust gasses. If exhaust gasses are present the head gaskets are blown and the vehicle is not worth fixing! All Northstar engines blow head gaskets sooner or later. Hope that helps! Jim

The fix is not as simple as new head gaskets like other cars. The cost to fix it with new head bolts may exceed the value of the car.

Absolutely! To do the job the engine and transmission must be removed from the bottom of the vehicle. Then you can pull the heads to move forward with the job. You need someone who is familiar with these engines. Several years ago a friend had the job done on his 98 Eldorado. It cost him just over $3,500. That was at a private garage, not the Dealer. Most dealers won't touch them anymore. These Northstar equipped vehicles are old enough now that they're not worth fixing anymore. Hope that helps! Jim