Got a P0446 which seems to be a vent prob. Autotap says blockage. Don't think this is a gas cap issue as that would vent the vacuum, not prevent it from venting. So..... where's the vent solenoid. I can isolate it and check operation. Seems to be the logical place to start.

 

Do you have a 2dr or 4dr? For the 4dr, it is located above the spare tire on the cross member. It will have 1 large vacuum line and an electrical connection. Drop the tire. Remove 1 bolt to detach the valve from the crossmember. For the 2dr, it looks like you have to remove the spare tire (if equiped with under vehicle spare) and it should be on the cross member. Again, it should have a large vacuum line and a 2 wire electrical connection.

I'd remove the valve and give it a good cleaning first. There is a foam filter that is under the rectangular cap and if that is plugged, it could cause this code. On my Bravada, the valve itself had failed open, causing this code.

 

Thanks very much. I can't believe that in my haste I forgot to identify the vehicle (I get frustated when anyone else does that). For purpose of record it is: 2000 2WD 4dr.

 

No problem, that's why I gave as much information as I could. Hope that it helps!