Questions and Answers
Lumina Code P0446
Q. I have a 1999 Chevy Lumina sedan with the 3.1 engine. My "Service Engine Soon" light came on and I had it diagnosed at a local parts store. The code was P0446 - "Evaporative Emissions control System Vent Control Circuit Malfunction". My question is - where and what components do inspect for this circuit?
Thank you,
JeffA. It could be many things, a loose gas cap, vacuum line off of fuel tank or evaporative charcoal canister, bad evaporative vent solenoid or wires to it. There is a special procedure for this code that may require putting the Evaporative Emissions System under pressure with nitrogen. Not something you can do in the backyard. If you pump oxygen into the tank you are creating a potential bomb waiting to happen!! I would suggest you look at all hoses for anything obvious and if you don't find anything, go to a dealer to have it checked out.
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