What I was told by the staff at BMW SPECIALTY SHOP B
On January 28, exactly 1508 miles after the $1200 diagnostic, I brought the car back to BMW SPECIALTY SHOP B with the oil light on, complaining of this new oil consumption problem.
They called me at noon that day to say that the cylinder leakage numbers were very high on cylinders 1, 5, and 6- from these figures I was told that I needed to have the motor rebuilt or replaced at a cost of about $6000.
They wanted 78 dollars to tell me that, which I scoffed at- so they re-wrote the invoice as Service Goodwill for the copy I received on the 29th.
Every BMW service rep, mechanic, or technician I have talked to (including The President of SHOP B prior to November 26th of last year) has said that if the oil is changed regularly, and basic maintenance intervals are observed, the 3.5 liter BMW motor should be good for upwards of 200,000 miles before requiring rebuild.
However, burning oil at the current rate probably causes the vehicle to violate state emission regulations, cylinder damage may be compounded by continued operation in this condition, and the excessive hydrocarbon emissions will lead to immanent failure of the catalytic converter. In short, I am left with a motor requiring a re-build at only 105,000 miles
The President of BMW SPECIALTY SHOP B did (on the 29th of January) come around after a lengthy discussion of possible causalities to an admission that there was some remote possibility that the piston or rings might remotely have been damaged during their work, but continues to insist that the fault lies with whoever had previously serviced that spark plug, because their alleged mis-handling was responsible for the breakage of the spark plug.