Some customers may complain about an unusual noise coming from the engine compartment for about 20 seconds after a cold engine start. This noise is a normal engine operation for improved exhaust gas emissions. The noise does not indicate a malfunction. ACCELERATED WARM-UP SYSTEM (AWS): All SKYACTIV-G engines adopt AWS to reduce exhaust gas emissions immediately after a cold engine start. AWS increases the engine idling speed and retards the ignition timing for about 20 seconds after the cold engine start to quickly warm up the catalytic converter. The customer may identify the engine sound
during the AWS operation as a unusual noise.
