Although the battery survived for many years on a maintainer, it died after a few days more despite being on the charger. So, replaced the battery and also ordered a tensioner for the AC belt.

FCP Euro sent me a near empty box, only an unidentifiable steel cap in it..... I went ahead and swapped the belts as they were looking brittle. The customer service guys had the tensioner on my front porch the next day! Pretty good service from them over the course 8 orders I have to say. Parts arrive significantly quicker than from Pelican or Autohause.

The Nav screen only flickered when I got the car running. It revived for a few minutes but nothing since. Yesterday I put in a new screen which had been languishing in a closet, no luck. Ordered a replacement Nav from an Ebay source.

Yesterday I ran it on the beltway for a bit and nothing wrong but on restarts I still get an initial error with CEL, the engine stumbles for a few seconds, revving it gets it going and it settles in to a steady idle. My guess is that this will be the case until the Vanos seals wear-in a bit more. I will reset the codes once more and report them here.

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2003 4.4i black ext./black int./black headliner (kid's runabout)
2014 535d X-drive, M package, silver/black interior

Sold but not forgotten:
2009 E70 35d, black ext./black int./black headliner (sold 2021)
2006 4.8iS Le Mans blue/cream int./black headliner, SOLD in 2012 sadly...

Other hardware:
2015 Cayenne S (wife's new DD and definitely wroooommmmm)
2016 Tundra 1794 edition crew cab, luxo hauler
2005 Tundra crew cab, weekend hauler. Sold after 150k very happy miles.