1999 blazer Code P0446

SES Light came on and i scanned it and code P0446 is coming up, Evaporative Emission Control System Vent Control Circuit Malfunction anyone know if i can fix this myself or need to take it in?

always try the gas cap first

i checked gas cap, i also deleted the code with my scaner and it came back the next day.

I currently have the same problem and hope that someone can give us some direction on where to go from here. I had posted a question on this a while ago and received nothing, so hopefully someone knows what can be done. Mine has just been sitting in my garage since. If you take it in please let me know what they say.

i checked gas cap, i also deleted the code with my scaner and it came back the next day.

did you try a new gas cap?

I have gotten similar codes. Check gas cap, vacuum solenoids and valve, check all vacuum connectors dealing with evap emissions, check vac canister, check gas tank filler tube for rust holes......

Cobra- Yes I tried a new gas cap. From my understanding, a code P0446 is a mass leak and just the gas cap typically won't cause the code for a mass leak.

Knucklebuster- Wow, sounds like I have a lot of checking to do. Where are the vacuum solenoids and valve located? I thought I checked these, but just received information that confused me and makes me think I checked in the wrong area. Thanks