Cold Start Engine Speed Monitor Operation

Once the waiting period is complete, the monitor compares the average difference between desired and commanded spark to a calibrated threshold that is a function of the engine coolant temperature at start. If the difference exceeds the calibrated threshold, a DTC sets.

• DTC: P050A Cold start idle air control system performance
• Monitor execution: Once per driving cycle, during the first 15 seconds of a cold start
• Monitor sequence: None
• Monitoring duration: Data gathering occurs during the first 15 seconds of a cold start. The decision to set P050A is made 300 seconds after start. This delay gives time for other diagnostics (for example, misfire monitor) to determine if another DTC should set instead of P050A.