93 grand am 3.3 coolant help

[albischof]

My 93 grand am, 3.3 ltr. is creating too much preasure in the coolant system and blowing coolant out the radiator cap before the car reaches operating temp and especially during excelleration. What would cause this problem????? I changed the thermostat and the radiator cap and it's still doing it. Any info would be greatly appreciated.

[GTP Dad]

Make sure you got all the air out of the system. Too much air will cause the issue you discussed. If there is no air in the system then check to make sure you don't have a bad radiator cap. Finally you may want to do a compression check to see if you have a bad head gasket. This too can cause a pressure build-up in the system.

[albischof]

Thank you, I have been told that air could be trapped in the system, and I have run the car to release the air, I was told there are bleeders, but I have been unable to locate any if there are any even on the water pump. so I ran the car with the cap off for about 15 min. to hopefully bleed the system and this has not worked. As for the heads I just changed those gaskets too and do not have any problems there. I will try "bleeding" the system again.

[GTP Dad]

Look on the top of the thermostat housing. There should be a bleeder screw there. Also make sure you run the heat wide open when you are trying to get the air out of the system. Running with the cap off should do the job but the heater may trap air.