Q: After i full with gas I got code P0420

asked by on January 28, 2017

After I full with gas I got code P0420

Hello, thank you for writing in. When there are issue with the vehicle’s gas recirculation system, the engine may pull in excess exhaust fumes. This will cause the engine to run rich and make the catalytic converter unable to compensate for the fumes coming through. You may also have an issue with the gas cap which is responsible for regulating pressure inside of the tank. Both of these components should be tested starting with the fuel cap. Only further inspection will tell since there are no other diagnostic codes to help you narrow in on what the issue really is. For more diagnostic help, contact our service department to schedule an appointment.

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