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P05D8

PCV Regulator Valve Control Circuit Open

The control circuit of the electrically actuated PCV regulator valve has an open circuit. The ECU cannot adjust crankcase ventilation flow against engine load - typically affects emissions and oil consumption under high load.

  • Check engine light: Yes
  • Emissions related: Yes
  • Repair difficulty: easy

Common causes

Ordered by how often each turns out to be the cause.

  • Open in valve or harnessCommon
  • Pin pushed back out of connector bodyLess likely
  • Cracked solder joint inside the module or sensorLess likely

Parts involved

  • PCV Regulator Valve

P05D8 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.