Hi Super Turtle, thanks for your valuable input.
Yes, mine is a 280SEL, and the reason why it was not listed on Parts Shop was probably this lower capacity model is not popular or unavailable in US. However, 280s' and 300s' are the norm here in Singapore.
Back to the part number. Yes, I did suspect that the original part number might have been updated from 011 to 002. And I am quite certain that it is part of the idle control system of my car.
I have tried using Parts Shop, but it wasnt an accurate guide because it does not list parts for my 280SEL. But I'll work further on your inputs, thanks!