I lost track here a bit as I really have never read the theory of operation of the valve. I have neutered every one that got in my way; making the car run good. They were designed only to take the fuel away in decel. Basically it bypasses the airflow meter.
No US model used any such devise so I have never seen a wiring diagram. Its vacuum controlled, with the vacuum coming from an electricallyt controlled switch over valve. I don't know who does the control but it should only open when in decel. Decel is defined as closed throttle, high rpms. From the engines stand point there is never a time for this valve. So bypassing it is an appropriate test mechanism. If the car exhibits the same problem with it blocked then its not part of the problem.
Bosch Master, ASE Master, L1
33 years MB technician
Last edited by stevebfl; 01-24-2003 at 10:11 AM.