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check engine code PO442


floridasun4me
03-19-2018, 07:12 PM
my sienna is showing the code PO442. i changed the gas cap with a cheaper priced one and the light came back on. would it be because i am using a cheaper version (6-10$) than an original factory ( @36$) gas cap?

Brian R.
03-19-2018, 11:30 PM
It is possible that your cap needs to be a Toyota cap.

It is also possible that is a different problem than your gas cap. P0442 is a code indicating a small leak.

Check for cracks, deformation and loose connection of these parts:
Fuel tank
Charcoal canister
Fuel tank filler pipe
Hoses and tubes around the fuel tank and charcoal canister

Check filler neck for damage or rust hole
Check vacuum hoses between vapor pressure sensor and fuel tank, charcoal canister and VSV for pressure switching valve, and VSV for pressure switching valve and charcoal canister.

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