Hi;

2000 S-10 with a 2.2 motor. Vehicle ran hot and had to replace
Radiator, Water Pump, Thermostat, and Radiator Cap. The car still runs
hot. Another wierd thing is that the truck wasn't driven for three
days, and when I went to check the coolant, there was still a lot of
pressure in the radiator. When I removed the cap, I felt all the
pressure escape, and the coolant was close to the top of the neck.
Then I watched the coollant in the radiator drop about 3 to 5 inches
over the next 30 seconds and held off there.

I have used a coolant pressure tester and pumped the system up to 17
lbs. It held the 17 PSI for 30 minutes without any leaks or loss of
pressure. There is no oil in the coolant or water in the oil, so I
dont think it is a bad head gasket. I would think if the head gasket
was bad I would have a loss of pressure when I pumped it up.

I am wondering if the Radiator cap could be defective so that the
system sends coolant to the reservoir when it gets hot, but is not
drawing it back in when cool. Any advice or reccomendations would be
appreciated.

Thanks
Pat