Factors For Smooth Running Control

WARNING: This page is about a different car, the 2018 Infiniti Q60. However, it is still accessible from the selected car via links, so may be relevant.

Factors affecting the smooth running control:

Engine speeds and engine load
Engine coolant temperature
Detection of rough roads
Synchronization of injection and ignition order
Crankshaft position sensor adjustment

Engine Speeds And Engine Load

ECM sets a standard value of the time between two combustions, according to engine speed and engine load.

Engine Coolant Temperature

Since the cold start permits more misfires compared with warm-up, ECM measures engine coolant temperature.

Detection of Rough Roads

Vibrations from the drive train resulting from rough roads adversely affect the revolution under the specific engine speed and engine load. Therefore, it is required to extend the tolerance of smooth running control when driving on rough roads. ECM receives a wheel speed signal (detecting rotational differences among wheels) from the ABS actuator and electric unit (control unit) unit via CAN communication.

Synchronization of Injection and Ignition Order

ECM monitors misfire in each cylinder according to signals from crankshaft position sensor, intake camshaft position sensor, and exhaust camshaft position sensor.

Crankshaft Position Sensor Adjustment

The tolerance of the smooth running control is decreased after the completion of crankshaft position sensor adjustment. This allows the smooth running control to be adapted to rough idle of engine. ECM memorizes normal engine speeds of the deceleration timing (accelerator pedal not depressed) and uses the memorized speeds as comparison data for misfire detection.