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

Catalyst Light Off is a time for catalyst to reach the target temperature that it is functioning effectively.

When engine is cold, ECM (PCM) performs catalyst light off offset to increase the temperate of it up to proper temperate that catalyst is functioning properly.

ECM (PCM) offets idle RPM more than 50 RPM than normal for catalyst light off.