Q: Evaporative Emission Control System Leak Detected (Gross leak, check fuel cap, piping etc): Code P0455

asked by on March 06, 2017

My car has been suffering with terribly low mileage. after a computer test i got this error and i was told it is the reason for the poor mileage. I checked the fuel cap; it was broken and the O-ring was not installed so i changed the fuel cap and installed a new one. the "Check Engine" warning on the car's dashboard disappeared but it got back on the day after. even after changing the bad fuel cap i still get the same error code "P0455" on the computer test. what do i do next?

My car has 93205 miles.
My car has an automatic transmission.

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Hello, thank you for writing in. The vehicle is experiencing a leak either with the EVAP system, or pertaining to the fuel tank. A visual inspection of the fuel tank and filler neck can rule out any physical damage in that area. You may also have to perform and evaporative emissions leak test. This will tell you where the leak is coming from, and you can take further diagnosis or repairs from there. You may want to pay special attention to the purge valve and do some further inspection on it as well. For more help, contact our service department to schedule an appointment.

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