code p0449 on 2007 Chevrolet Silverado 1500

2007 chevy silverado classic. code p0449 light will come on and after a few days go off, then come back on. I have taken the solenoid and canister off and cleaned. also looked for leaks. have checked and tightened gas cap. when i reset the light it will stay off at least a day before coming back on. Thanks

Get Your Car Fixed at a RepairPal Certified Shop.
We certify shops based on expertise, quality work, and verified customer reviews
2 answers
There is a service bulletin for the code p0449 setting on your 2007 Chevrolet Silverado 1500. The number is #09-06-04-028. The repair suggested is to replace the canister vent solenoid and relocate it to a position near the fuel filler neck. This may help but there is know way to tell for sure if this will correct your particular issue.
what is P0449