Powertrain
generic / SAE
P04DB
Crankcase Ventilation System Disconnected
A pressure or flow sensor in the crankcase ventilation (PCV) circuit reports atmospheric conditions where it should see crankcase or intake vacuum - the hose between crankcase and intake is disconnected, cracked, or open. PCV no longer routes blow-by gases into the intake, increasing oil mist emissions and risking oil leaks.
SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number4 / DB
Possible causes
- PCV hose pulled off or split high
- Oil filler cap missing or loose medium
Inspection / repair
- Difficulty: easy
- DIY: possible
- Estimated cost: 40–200 €
- Estimated time: 0.3–1 h
- Component: pcv hose
- Component: pcv valve
- Component: pcv sensor
- MIL / check engine light
- emissions-relevant
Sources
References
sae:J2012