How do you diagnose an overheating problem on a 93 grand am quad 4 we have relaced the radiator and the thermostat?

Answer 1

If you replaced the thermostat and radiator, the next step after this would be to replace your water pump, radiator pressure cap, check condition of ALL radiator lines and hoses, and replace as necessary. A hose should be replaced if it feels really soft, or if it starting to crack due to the aging rubber they are made of. Once you replace the parts described above have a certified mechanic run a pressure test on your vehicle's colling system. If you still overheat you might have an oil problem. Oil dissipates MOST engine heat but not well enough to do the whole job, which is the reason cars need cooling systems. Once your cooling system checks out see what a mechanic will tell you and I believe the most likely cause would be an oil problem. If oil is not getting to the cylinders properly the engine can overheat really fast and could possibly seize so be careful! Also note you may want to replace the timing belt as well if your car is at least 60,000 miles, or you have never replaced because on most cars the water pump is right near the timing belt. Replacing water pumps is extensive work in labor terms, so you may want to replace the timing belt because if you replace the pump and the timing belt on separate occasions, you'll have to pay the labor both times unless you have the know how to do it yourself.