Toyota Repair/P0446


Working on a friends 2001 Corolla. Im a fairly competent DIY-er Periodically on his car P0446 comes up. Use my basic OB 2 code reader. Since we don't have the emissions regs in our area just reset it but think it's time to further exam it. Cap is still original but still seems good(?). Trying to find problem and hopefully( maybe not) save replacing the vapor canister. Noticed that when the gas cap is removed no pressure is released. Would that be the VSV at the canister? Is that also the same as the "purge solenoid(Vent Valve)? Are these accurate assumptions. Or will this have to go to dealer.

A purge VSV malfunction should give you a P0441 code, since you are only getting the P0446 which is a leak at the tank and it's associated VSVs and hoses, the canister may be the cause, it is also very common for the fuel cap not holding pressure to be the reason, remove the fuel cap and inspect the filler neck area on top for any damage, try replacing the fuel cap with an OEM part or equivalent, clear the code and see if it comes back

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Ted Ritter


I have more than 28 years experience as toyota technician, I will be able to answer most questions related to the Toyota product line up to the present year models,I am located in the US but welcome questions from other regions of the world. When asking a question please provide specific information: year,model, engine,transmission information. Provide as much information as possible including a brief repair history if possible. I have been a volunteer here for more ten years an have answered over 16,000 questions helping Toyota owners with their problems and save thousands of dollars without any compensation, some of my answers are published on many other websites including google and various automotive forums. DONATIONS ARE VERY MUCH APPRECIATED, IF YOU HAVE RECIEVED HELPFUL INFORMATION PLEASE MAKE A DONATION. AS OF TODAY (JULY 22, 2014) ALL REQUESTED GRAPHICS, ILLUSTRATIONS, DIAGRAMS, PHOTOS, WILL REQUIRE THE MINUMUM DONATION UP FRONT.


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