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Q: Check engine light on

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My check engine light is on p0442 I changed the gas cap and the check engine still on and I checked the fuel pumps there fine what could it be

My car has 52897 miles.

A: The code P0442 is for a very small leak in ...

The code P0442 is for a very small leak in the evaporative system of the fuel tank and its vent system. A leak in the gas cap is the most common cause of this code and the gas cap or the lip where it seals on the tank cannot be damaged in any way. A leak check of the system can be done with a smoke machine that can detect the leaks and then a repair can be done. I would have a certified mechanic, diagnose the Check Engine Light so that only the necessary repairs are made.

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