When you get a check engine light, your parts store can test it with a little electronic device – ask for the check engine light tester.
They go by many names, but look for EVAP Valve or Vent Valve Solenoid & Purge Valve Solenoid. The one in the rear of the car, near the gas tank, is known as the “Vent Valve Solenoid Canister.” The one in the engine compartment is called a ” Purge Valve Solenoid.”
Replacing the one in the engine compartment did the trick. I’d start by replacing that one first then test it.
$25.97 Vent Valve Canister (fuel tank one)
$35.72 Purge Valve (engine compartment one)
GM Dealer quote: $281.00
I saved $219.31!