Active Exhaust Actuator

The active exhaust actuator operates a valve in the exhaust pipe, the valve is the acoustic exhaust valve.

The position of the acoustic exhaust valve is set by the Powertrain Control Module (PCM). The position depends on engine speed and the Accelerator Pedal Position (APP) sensor. On vehicle start up, the active exhaust valve is always open, to enhance the exhaust sound. The PCM closes the active exhaust valve to reduce exhaust noise at engine speeds greater than 900 Revolutions Per Minute (RPM). For example, cold start, or fast idle conditions.

It is possible to start the vehicle in 'quiet mode'. After ignition ON (Power Mode 6), wait 5 seconds before engine start (Power Mode 9). The active exhaust actuator closes the valve.

When the active exhaust system is activated by the PCM, the acoustic exhaust valve is open over the majority of the engine speed and load range. The acoustic exhaust valve is closed when driving in middle speed and load conditions, then open at high speed and load conditions. This serves to enhance the sound quality in the vehicle and reduces back pressure to enhance engine performance. This method can further enhance the sporty driving experience. The PCM disables the active exhaust system during specific engine operating conditions.

For information on the APP sensor and the Crankshaft Position (CKP) sensor refer to: ELECTRONIC ENGINE CONTROLS