DTC P0446 Evaporative Emission (EVAP) Vent System Performance
The vehicle control module (VCM) monitors the performance of the evaporative
emission (EVAP) system by applying a predetermined level of vacuum to the
EVAP system and monitors the vacuum decay rate. The VCM sets this diagnostic
trouble code (DTC) if the vacuum decay rate is more than a predetermined
value. The VCM monitors the amount of vacuum and the amount of pressure
in the EVAP system by monitoring the fuel tank pressure sensor. For
this DTC, the VCM turns ON both the EVAP purge valve and the EVAP vent
valve when the Conditions for Running the DTC are met. This applies
an engine vacuum to a closed EVAP system. The VCM turns OFF both the
EVAP purge valve and the EVAP vent valve when the system reaches a correct
amount of vacuum. The EVAP system should quickly RELEASE the vacuum
in the EVAP system with the EVAP purge valve OFF and the EVAP vent valve
OFF (open). This test indicates a blocked or restricted EVAP vent path
if the EVAP system fails to release the vacuum quickly enough.
Evaporative Emission (EVAP) how to find a leak without replacing canister on chevy silverado 1500
Insert your key into the ignition, and turn it to position "A" (Run/On) without cranking the engine.
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How do I fix my Evap problem?? I changed the PCV still no luck. I need to pass inspection in 1 week.
my 2000 chevy silveado's service engine soon light just came on and the OBD code is P0446 which according to the book I have is an EVAP Emission control system vent circuit malfunction. Any help is appreciated as to what I have to replace. Also is it ok to continue driving this for the time being until I get this fixed. thanks
Who can offer a solution, not just more info about the problem?
I have the same problem on 2003 silverado 4.3L
2003 Chevy Silverado 5.3L VORTEC V-8 - 12,000 miles - exact same problem - is this something that can be fixed at my house or must I take it to the dealer?
location of solenoid
I understand this has to do with emissions purge. I replaced gas cap... no luck. I had it checked by the dealership, and the stated they noticed moisture in the lines when inspected. Should I replace both the NVLD pump and Solenoid?... or just one or the other? Where are these located? How difficult will it be to do do myself, or should I just have a mechanic do it? How much time should it take? Any other suggestions would be greatly appreciated as well.
where is the evap. purge locatd on 2002 chevrolet located?
fuel leaking from the top left of fuel tank
show location
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