P2422

P2422 sets when the EVAP system monitor runs a vent-valve seal test and determines the canister vent solenoid is stuck in the closed position, which prevents fresh air from entering the charcoal canister during purge and pressurizes the tank instead of allowing the calibrated airflow the monitor expects. The vent valve lives at the back of the vehicle near the canister and spends its life caked in road grime and water spray. Cheapest-first ladder: command the vent valve open and closed with a bidirectional scan tool and listen for the click, then if there is no click pull the connector and ohm the solenoid coil (typically 20 to 40 ohms) and check for 12V on the supply wire with key on. If the valve clicks electrically but still fails the monitor, the problem is mechanical, which on this exact code is almost always mud, leaves, or a wasp nest blocking the vent inlet filter, or internal corrosion seizing the valve plunger. Caveat: do not condemn the valve until you have visually inspected the vent inlet and the canister itself, because a saturated or contaminated canister will mimic the same failure.

Vehicle-specific patterns: 2005-2013 GM trucks and SUVs (Silverado, Tahoe, Equinox) are notorious for spider webs and mud plugging the vent filter mounted near the spare tire, and the fix is often a cleaning rather than parts. 2007-2014 Ford F-150 and Expedition see the vent valve itself corrode shut from being mounted directly to the canister behind the rear wheel. 2006-2012 Jeep Wrangler and Liberty trap water in the vent valve from off-road use. 2008-2015 Subaru Outback and Forester have a known issue where the canister itself absorbs water and the vent valve plunger sticks. Estimated repair: $80 to $320.