Some vehicles may experience a check engine light on with DTC P0172:00 stored in the PCM memory. This normally occurs during the fast idle immediately after starting the engine or after the fast idle lowers to a normal idle. DTC P0172:00 - Fuel trim system too rich. Due to improper PCM control logic, the fuel injection amount may be improperly compensated when the engine start is not smooth and due to low quality fuel.
