I have a 1996 Pontiac GrandAm SE with 156,000 miles. It has the 2.4 liter engine. It overheated on my wife a few times and she just kept adding water, without telling me she was having trouble with it. Long story short, she got it REALLY HOT.I have changed the thermostat and water pump but now it has a ticking after it warms up and it still overheats. There is no water in the oil and no signs of water or oil getting into the exhaust.I've changed the oil and antifreeze also.I've tried to hook up an OBDII code reader to it but it does'nt bring up the Vehicle icon to acknowledge a good power connection and displays an ERR on the display. It has always worked fine in the past on this car and it still works on other cars. So I think the patch cable is in good shape and the vehicle DLC does not show any visual damage. Any help on this matter would be greatly appreciated. Thank You
I would test the fan clutch first. When the vehicle is warm, shut it off and test the resistance to turning the fan. It should have considerable resistance with it warm. Another test is, If the clutch fan is the coiled bi-metal spring type, it may be tested while the vehicle is being driven. To check, disconnect the bi-metal spring, and rotate the spring 90 counterclockwise. This disables the temperature controlled free wheeling feature and the clutch performs like a conventional fan. If this cures the overheating condition, replace the fan clutch.
Another thing that can help is to check the compression on each cylinder. If the engine overheated too much it could have warped the heads and caused the head gasket to leak. Cracked heads is another posibility.