Evap Tank Solinoid

[05GMC4DR]

Where is the PSI solinoid located. Ive heard that its in the tank but Im hoping that maybe its on top somewhere where it could get knocked around or a wire pinched or something.

[jedcooper]

Okay, not 100% but here goes...

 

There is a a solinoid on the exterior of the tank or close to it, and another on the the intake manifold.

That's the only two I'm aware of. There is a connection on the fuel pump that monitors tank pressure. The system checks for leaks by using manifold vacuum (from intake solenoid) and closing evap solenoid and checking for vacuum in tank. The rest of the time the evap solenoid is pretty much open to let outside air in to replace lost volume as tank level drops, and to evap fumes collected in evap canister. So it gets plugged with junk from the outside.

 

I listed all that so you can trace your evap lines and find it, because GM moves it around year to year and model to model.