OBD-II reference

All 9.533 generic OBD-II codes, explained in detail.

Causes, inspection steps and sources — a comprehensive DIY archive. Created and maintained with love for the detail. Good luck and have fun!

Powertrain generic / SAE

P2450

EVAP System Switching Valve Performance/Stuck

The EVAP switching valve does not respond to commands as expected. The valve is mechanically stuck or unable to switch between purge and vent paths, blocking proper leak diagnosis.

SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number4 / 50

Possible causes

  • Mechanical failure of valve high
  • Contamination preventing motion medium

Symptoms

  • Check engine light on
  • Possible smell of fuel near tank or engine bay
  • Failed emissions inspection
  • Loose-cap warning may appear

Inspection / repair

  • Difficulty: medium
  • DIY: possible
  • Estimated cost: 120–500 €
  • Estimated time: 0.5–2 h
  • Component: evap switching valve
  • Component: evap canister
  • MIL / check engine light
  • emissions-relevant
  • drive cycle required

Sources

References

How to read OBD-II codes

The first letter names the vehicle system, the second digit distinguishes generic from manufacturer-specific, the remaining digits group fault area and number.

PPowertrain: engine, transmission, emissions
BBody: chassis trim, comfort, interior
CChassis: suspension, brakes, steering
UNetwork: CAN, control modules, communication