P2418
EVAP Switching Valve Control Circuit Performance
The evaporative switching valve — used on multi-path EVAP systems to route purge or pressure-test flow — does not respond as expected. Self-test fails because tank pressure does not change in the calibrated direction.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: medium
Symptoms
- Check engine light on
- Possible smell of fuel near tank or engine bay
- Failed emissions inspection
- Loose-cap warning may appear
Common causes
Ordered by how often each turns out to be the cause.
- Switching valve failedCommon
- EVAP line blocked or kinkedPossible
Parts involved
- EVAP Switching Valve
- EVAP Lines
P2418 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.