If you bought e53 it's at least 14 yr old. It will require constant upkeep but not necessarily that difficult nor expensive.

Example. Wife's X5 alternator just quit output voltage at low RPM. I refurbished mine two years ago same problem $20 kit to replace the slip rings and back in business.

Search awr-fix: in title to find the repair for left tank sender unit

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