Cooling system schematics/overheating
Asked by GuruXVXTB Oct 15, 2018 at 12:28 PM about the 1999 Pontiac Grand Prix 4 Dr SE Sedan
Question type: Maintenance & Repair
Hi I have changed the thermostat cleaned
the rubber hoses and reservoir ,flushed
system an refilled but still seem to have a
overheating issue, water pump was replaced
beginning of year heater works fine cooling
fan is operational and no head gasket
problem ( atleast that I can tell)no milkshake
3 Answers
Correction that is a grand am not grand Prix.
Probably air trapped in the cooling system. Very common problem when refilling the cooling system and it won't work right until the air is out. Did you use the bleeder valve by the thermostat? Sometimes helps to drain the system and refill it again, slowly, with the car facing uphill or the front wheels up on a bit of a ramp to make the air come up out of the engine more easily. If all else fails you may need to take it to a shop that has the proper vacuum equipment needed to draw the air out of the system while its filling.
Florence01 answered 5 years ago
There is a cooling sensor that may need replaced. It fixed my problem in my 2003 Grand Prix
