I bought an CanOBD II Diagnostic code reader for my 2001 Buick Century Custom and it came up with two codes; P0446 Evaporative Emission System Vent Control Circuit and P0141 02 Heater Circuit (Bank 1 Censor 2). There doesn't appear to be anything leaking on the engine anywhere, however; there are some small rusted out holes in the exhaust system which I believe are located in the muffler or catalytic converter and now after taking my car for inspection (which it failed) there appears to be a hole towards the front of the car because the sound is louder in the front now instead of just the back.(hhmmmm, curious)Does anyone have any suggestions? My husband would like to make the repair himself in order to save money (which is very scarce these days), How do we locate the 02 censors and heater circuit?How probable do you think that the muffler or catalytic converter is the cause? Thanks for your help in advance. Sharon
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2001 Buick Century Question: Diagnostic codes
Answer #1mastertech6371 July 20, 2010, 20:09Master
446 is the vent soloniod. it is a common failure part. you can purchase it at your local gm dealer and it is located in the back of the car by the charcoal cannister.
the o2 sensor is behind the cat under the car. you can get that at any auto parts store.