I unscrewed my radiator cap to test my head gasket (the engine was hot because I had just drove it) and there was little to no pressure release when I unscrewed the cap? Also when the trucks hot and I have the cap off, I see no movement of the fluid?
My car has 124100 miles.
My car has an automatic transmission.
Hi there. Most of the time, when there is no pressure in the radiator it is caused by a small leak or an obstruction within the coolant system. It is also possible that the water pump is failing to push coolant through the engine. However, in most cases, those problems also show up as an overheating problem. It’s a good idea to complete a pressure test to determine if a leak exists. If you can’t find the source of the problem, have a professional mechanic inspect your coolant system.
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