Low Idle Air Flow Test
When the cold start emission reduction monitor is enabled, the powertrain control module (PCM) commands the idle air control system to increase the RPM, which elevates engine air flow. While this cold start emission reduction elevated air flow is requested, the low idle air flow test compares the measured idle air flow from the mass air flow (MAF) sensor to the commanded idle air control strategy. For the purpose of detecting low air flow concerns, the low air flow test uses the measured air flow and the commanded air flow to create a low air flow index.
Low idle air flow test operation: -
- DTC: P050A cold start idle air control system performance
- Monitor execution: Once per driving cycle, from start up with the cold start emissions reduction active
- Monitor sequence: none
- Monitoring duration: 7 seconds
Low idle air flow test entry conditions: -
- Engine coolant temperature is between 4.4°C (40°F) and 82.2°C (180°F)
- Barometric pressure is between 76.2 kPa (22.5 in-Hg) and 105 kPa (31 in-Hg)
- Engine off soak time is at least 50 minutes
- Throttle is at closed position