my resivor cap blows off when driving
From the coolant tank? Most likely over filled or caps too janky to stay but could have too high of pressure in the system
HMMM, 03 PT Cruiser blowing off recovery tank cap, sounds suspiciously like a blown headgasket, if your into DIY you can purchase a block test kit from your local parts store or have your favorite shop check it for you.
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