DTC P050A: Cold Start Idle Air Control System Performance: General Description

The Powertrain Control Module (ECM/PCM) along with the Electronic Throttle Control (ETC) controls ignition timing and engine idle speed during cold engine start (cold soak). The ETCS controls the throttle motor to open and close the throttle valve to achieve the target idle speed. In addition, the ECM/PCM controls (retards) ignition timing and the ETCS increases the intake air amount to quickly increase the catalyst temperature at cold start to reduce emissions.

If no DTCs are present, inspect the intake air system for air restrictions, vacuum leaks, and damage. If no concerns are present, clear any DTCs and verify the engine coolant temperature is below 37.8°C (100°F). Allow the vehicle to soak for 2-3 hours if necessary for the engine coolant temperature to fall below 37.8°C (100°F). Start the engine without touching the accelerator pedal and allow the engine to idle for 6 minutes in park. If no DTCs are present and the malfunction indicator lamp (MIL) is not illuminated after idling for 6 minutes.