PCV Valve
Meters crankcase vapour back into the intake under controlled vacuum. A failed valve or split hose is an unmetered air leak by definition, which is why it appears so often among the causes of lean fuel trim codes — and why it is worth checking before a sensor is condemned.
Also known as: pcv, positive crankcase ventilation valve, crankcase breather, breather valve, oil separator valve
Referenced by 31 codes
Codes involving this component (31)
- P0171 System Too Lean — Bank 1 High
- P0174 System Too Lean — Bank 2 High
- P2101 Throttle Actuator A Control Motor Circuit Range/Performance Stop driving High
- P04DB Crankcase Ventilation System Disconnected Moderate
- P04E2 Crankcase Ventilation Hose Connection Sensor Circuit Low Moderate
- P04FB Crankcase Ventilation Hose Connection Sensor Range/Performance Moderate
- P04FC Crankcase Ventilation System Performance Moderate
- P0505 Idle Air Control System Moderate
- P0507 Idle Air Control System RPM Higher Than Expected Moderate
- P051B Crankcase Pressure Sensor A Circuit Range/Performance Moderate
- P051C Crankcase Pressure Sensor A Circuit Low Moderate
- P051D Crankcase Pressure Sensor A Circuit High Moderate
- P2072 Throttle Actuator Control System — Ice Blockage Bank 1 Moderate
- P2177 System Too Lean Off Idle Bank 1 Moderate
- P2187 System Too Lean at Idle Bank 1 Moderate
- P2189 System Too Lean at Idle Bank 2 Moderate
- P2279 Intake Air System Leak Bank 1 Moderate
- P2281 Air Leak Between Mass Air Flow Sensor and Throttle Body Moderate
- P2282 Air Leak Between Throttle Body and Intake Valves Moderate
- P051A Crankcase Pressure Sensor A Circuit
- P051E Crankcase Pressure Sensor A Circuit Intermittent/Erratic
- P051F PCV Filter Restriction
- P053A PCV Heater A Control Circuit /Open
- P053B PCV Heater A Control Circuit Low
- P053C PCV Heater A Control Circuit High
Other components in Air Intake and Metering
- Intake Air Temperature Sensor 83
- Throttle Body 69
- Throttle Position Sensor 58
- Intake Manifold Tuning Valve 56
- Mass Air Flow Sensor 52
- Intake Manifold 51
- EGR Throttle Valve 38
- Throttle Actuator Motor 34
- Air Filter 30
- Manifold Absolute Pressure Sensor 29
- Crankcase Pressure Sensor 14
- Crankcase Breather Hose 13
- Intake Air Heater 11
- Idle Air Control Valve 9
- Intake Air Oxygen Sensor 7
- Humidity Sensor 5
- Air Cleaner Inlet Actuator 3
Information, not instruction
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