OEM sports exhaust
 

I have a OEM sports exhaust on my boxster 2000 S. The exhaust has butterfly valves that open under vacuum through two actuators. Is anyone familiar with the system? One of the vacuum lines has melted and broken off, I would like to test the system before replacing anything.

The actuators work when I put a vacuum on then opening the butterfly valves. The vacuum feeds off the cars vacuum system and goes through a solenoid valve. I think this valve from on 12v. Does anyone know when this valve is meant to kick in?

I am think of installing a switch to control the exhaust 'manually' but would still like to know how the standard system is meant to work.

Lastly having said all of that, I assume that at rest (when the engine is off) the valves are closed and that when pulling a vacuum on the actuators it opens the butterfly valves.

On a 986, the system is designed to meet EU noise standards and will close the valve's, quieting the system at certain low speed ranges. If vacuum is removed from the valves, the system will default to the open or loud position.

So are you saying that if say the vacuum lines are disconnected, the butterfly valves will be open? Which will means when the car is off the valves are open? and only if a vacuum is pulled, the valves close?

Yes - all the time.

Yes, vacuum lines or not, valves are open when car is off.