Exhaust Flap Operation

Exhaust Flap Operation:

The exhaust flap system consists of the following:
- Exhaust flap with vacuum actuator
- Solenoid actuator valve
- Vacuum reservoir with check valve
- MS 41.1 control module

The electrical function of the exhaust flap operation is controlled by the MS 41.1 module.

At idle speeds - up to 2500 RPM: the exhaust flap is closed with vacuum applied to the actuator. This causes the exhaust gas to pass through the long resonator pipe, reducing the low frequency noise that is generated.

Above 2500 RPM: the exhaust flap opens. This allows the exhaust to pass through the short pipe which maximizes the backpressure effect to provide the best performance.

In the event of electrical or vacuum failure the flap will rest in the open position providing maximum exhaust throughput.