1993 Plymouth Acclaim • 4 cylinder 2WD Automatic • 250,000 miles

I had a new rad (1 week old) put in and 2 new different rad caps. 2 new thermostats, new coolant, 8 month old water pump installed. After driving driving a distance the temp. Gauge starts fluctuating from to 1/4 to just below 1/8 mark on the cold side range. When I open up the hood and leave the car running, the rad cap is warm and it seems that there is no pressure build-up in the radiator because I am able to open it without the coolant squirting out. Some people tell me that it is a head gasket problem but I am not sure. Because I there is no external leak and no white, sweet smelling exhaust coming out of the muffler. Does anyone have any ideas? Any input would be very much appreciated.
December 30, 2010.

Use a cooling system pressure tester, Autozone will loan it to you, this will reveal any leaks quickly. You can also get a block test kit there, this will tell you if hydrocarbons are present in the antifreeze, this would indicate a head gasket problem.

Dec 30, 2010.