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Q: Trying to pass emissions test. Failed once. Code P0449

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Trying to pass emissions test, failed, code P0449 showed up. Changed charcoal canister, vapor canister vent solenoid, gas cap, cleaned corrosion out of EVAP electrical connection cleared code and light came back on after 25KM, cleared and comes up yellow. Not passing emissions My car has 94000 miles.
My car has an automatic transmission.

Hello, thank you for writing in. Code P0449 will set when the system sees that the position of the vent valve, and the voltage for its position, do not match. There could be a wiring problem, a faulty hose, or a failed component. The code only gives a general idea of the area affected, so that a certified mechanic knows where to start a diagnostic procedure. The mechanic should have the specialty tools and techniques to pinpoint what exactly is causing the issue. If you need help identifying and repairing the issue, YourMechanic.com offers several options. We have trained mechanics that can come to your home, or place of business, and perform the diagnosis and repairs for you.

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