I understand all of that. That's not what I'm asking. What I want to know is how it works in the M104 in particular. Just by looking at it, I could tell that it separates/consolidates the two halves (1-2-3/4-5-6) intake plenum by closing/opening. So my questions are thus:
- What happens with the induction air when it's open and when it's closed?
- How is airflow inside the plenum affected when it's open and when it's closed?
- Under what circumstances does it open/close?
- What controls its opening/closing function? ECM signal? Intake manifold vacuum/engine load? Throttle position? All of the above?
- Humblejoe
said that a non-functional flap disables variable intake. Am I to understand that if the flap/resonance valve/whatchamacallit is broken, the intake camshaft phase controller is also disabled? If so, how are performance, driveability and fuel economy affected?