P2450 Evap System Switching Valve Performance/stuck Open

Code: P2450
Applies To: Most makes, generic code
Loose Cap Can Set It: Not named in our sources
Typical Fix: $210 to $251 at RepairPal

The EVAP switching valve is not working right or is stuck open.
A shop confirms it with the carmaker's EVAP test and a smoke machine before replacing parts.
Usually yes for now, but get it fixed soon and check for open recalls.

What The Carmakers Call It

EVAP System Switching Valve Performance/Stuck Open, as printed by Volkswagen Group of America

Causes Named In Carmaker Bulletins

Engine computer software on 2021 to 2025 F 150 PowerBoost, fix is a PCM reprogram and EVAP check (source)
Engine computer software on 2018 VW Tiguan, fixed by a programming update (source)

No source ranks these by how often they happen, so they are listed as the bulletins give them.

No source ties P2450 to the gas cap.

What The Fix Costs

The usual part for this code is the purge valve. Published estimates put it at $210 to $251 at RepairPal. The full table with every source and date is on the cost page. A diagnosis first keeps you from paying for a part you did not need, which is why we price readiness monitors and smog check before the fix.

Getting The Light To Go Off

After the repair the light goes off once the EVAP test runs and passes on three drive cycles in a row, and the code is erased after 40 warm up cycles, per CARB. The test only runs under set conditions such as a fuel level between about 15 and 85 percent, so it can take days.