I did inspection with mirror and had wiped oil from under it many times, so far it is leaking from the bottom on the vacuum pump lid itself and not from the O ring from behind ..... [wonder if 100k miles is "the normal" time for vacuum pump to start leaking ] .........

BAVAUTO have PIERBURG/ ixetic vacuum pump for $280 - [ or for $350 with the BMW PN# 11667545384 on the box] .......
Btw the EXACT and very same PIERBURG/ ixetic vacuum pumps at the BMW dealerships parts dep. sells from $440 to $509 bucks at 4 different in the Bay Area SF/CA bmw dealerships .... -----

some people did rebuilding the vacuum pumps with O ring from oil filter kit - check the link bellow
2002 E46 318i - N42 Vacuum Pump Repair

__________________

US
'01 BMW 330Cisport MT [1]
'01 BMW 330Cisport MT [2]
'96 Benz C280
'05 X5 4.4isport
'99 Benz SL50AMGsport
'89 Benz 300TE

EU
'93 E124 Benz 250TE Wagon Diesel Manual5sp.




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