more news... i visted the agent today, unable to swallow the fact that i could not find this valve!
it turn out that on the microfiche, there is an expansion valve belonging to the w124 chassis, and another to the m111 engine(thats my engine). i was shocked! that means there is 2 regeneration valve in my car!
the one belonging to the m111 engine is the very visble and conspicuous one, somewhere behind the ABS pump. It has a 2 vacuum tubes connected to it and a 2 pin electrical connector with the word MOT on top of the connector.
the senior mech i talk to later then told me the first one that i bought was for engines using a different kind of fuel injection or vapour control system. said something about HRM and another term which i cannot recall now. I cant recall which one my car belongs to also. can any experts help me recall those terms?
in other words, i have to get the other valve that was right in front of me all this while.
bad news is this bugger now costs 100+ instead of 30! and i got an extra valve.
just FYI, the "faulty" valve i have now cannot hold a vacuum even when idling. Is this an indication of failure?