radiator cap?
what are the signs of a bad radiator cap??...coolant keep flowing into the overflow tank and i think i see some bubbles...so chances are it could be headgasket prob...but i wanna try the simple thing first. so what are all the sign of a bad radiator cap??
a bad radiator cap would leak all the time - but they can also indicate other heating problems
for example - they should fail at a certain temperature or pressure - if it is leaking and you replace it only to find the engine is overheating,

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