Got a check engine light about 600 mile since changing fuel pump on my 2001 Silverado 1500 4x4 w/ 5.3. Read code with my Tech 2 and states a P0446 which is in the evap system. Possible problems are the evap cannister solenoid valve clogged. My question is how difficult is it to remove without taking bed back off. I know GM has a kit to repair problem but trying not to go to the expense. Has anyone replaced or cleaned the valve with success.