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Q: Check engine light is on with various codes.

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Check Engine light is on with codes P0440, P0441, and P0446.

A: Hello, all three of your codes are for the ...

Hello, all three of your codes are for the evaporative emissions system. The first thing to do is a good visual inspection of all the vacuum line from the intake manifold to the purge valve. Any torn rubber hose or cracked plastic hose will allow a vacuum leak and the test will not be able to be done properly. The hose going from the purge valve to the line going back to the task should also be inspected. The purge valve should also be tested, with vacuum applied to the engine side of the valve, the side going to the tank should have no vacuum applied to it with the solenoid not energized. The vacuum line connecting the purge line to the intake should be vacuum tested and should hold vacuum. If those check out, the fuel vapor system from the valve to the tank will need to be tested. This will need the aid of a mechanic with special equipment, so the shut off valve can be closed and a smoke machine can be connected to the system and inspected for a leak, by looking for smoke.

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