DTC Advanced Diagnostics: P2279: General Description
The positive crankcase ventilation (PCV) system reduces hydrocarbon (HC) emissions. The PCV system recirculates unburned air/fuel mixture (blow-by gas) into the intake manifold so that it is drawn into the engine and burned, thus reducing HC. The powertrain control module (PCM) estimates the amount of air inflowing from the PCV valve from the deviation between the inflow air amount of the intake manifold calculated from the manifold absolute pressure (MAP) sensor and the amount of air passing through throttle body measured using mass airflow (MAF) sensor. When the PCV hose is disengaged, the amount of air flowing from the PCV valve increases and the deviation also increases. The estimated air quantity of PCV is compared with the judgment value (upper limit value), and when it exceeds the more than the upper limit, it detects a malfunction and stores a DTC.
Monitor Execution, Sequence, Duration, DTC Type
| Execution | Once per driving cycle |
| Sequence | None |
| Duration | 11 seconds or more |
| DTC Type | Two drive cycles, MIL on |