You should absolutely be able to wrench your own car to buy a used 50i. Or at the very least have a good friend who can and works for beer money.

Stop leak will not help these engines. Oil conditioner that softens hardened rubber of the VSS has been proven to help greatly and I suspect will add 10-20,000 miles before needing to replace VSS.

Valid points on the hidden cause of why they are consuming oil but the primary supposition is heat not wear causing the problem. Heat cooks the VSS and the material chosen for the seals gets hard no longer makes a tight seal and oil goes from valve train into the intake.

People report that after vss job the consumption mostly goes away so that is the main concern as far as I'm aware.

I would not buy a n63 or n62 motor add not plan on eventually doing a VSS job.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)