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Cold Start Performance and Idle Speed Monitor

OBD System Description - Cold Start Performance and Idle Speed Monitor

System Description / Monitoring Procedure

Cold start performance monitor
The ECM retards the ignition timing and increases the idle speed to quickly increase the catalyst temperature at cold start to reduce emissions. The ECM monitors the idle speed for cold start. If the idle speed and ignition timing are out of criteria, the ECM will set DTC.

Idle speed monitor
The ECM controls the throttle actuator based on TP sensor input. The idle speed is controlled by the ECM based on various inputs. The ECM commands the throttle actuator to open or close the throttle valve in order to maintain the targeted idle speed. If difference between measured idle speed and the target idle speed is out of criteria, the ECM will set DTC.

DTC Description / Detecting Condition / Confirmation Procedure

P0506 / P0507 / P050A / P050B
Refer to DTC P0506 / P0507 / P050A / P050B:N32A. P0506

Idle Speed and Cold Start Performance Monitor

Operation






Enable conditions






Typical malfunction thresholds