the O2 stream can be questionable as its an old sensor and old sensors go lazy as time proceeds.

your best remedy would be to start with changing the plugs and swapping coils - once both runs fail then you are left with two possibilities - fuel or compression.

Thats the fastest way to determine the fault with the least expense.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)