thepontif

There's a SUPER long back story to this, but my '08 550i sat for over a year and a half and wasn't started...because the alternator oil seal blew and I decided I was going to disassemble things a little at a time and replace the seal. But two teenaged daughters and the ensuing challenges prevented me from having any time to think about it so it never happened.

Anyway, long story short, in spite of the fact that it was running just fine a year or so ago (when I poured oil in and caught it in a pan as it ran) it will not start, now. One entire bank of cylinders (Bank 1) won't run. Fuel is getting there, but no firing. I've checked obvious stuff like electrical connectors, etc. and nothing obvious is wrong. I got a litany of codes, many of which are not entirely clear, but a couple were clear and referred to the 02 sensor and/or cam shaft timing or position sensor.

But I can't figure out what would change all on its own that would kill an entire bank of cylinders. But I'm also thinking the fact that it's an entire bank might narrow the range of possibilities. I know this is a very specific problem, and it might be that folks who haven't actually experienced it or something very similar could only guess. But at this point I have no earthly idea what direction to go.

Any help would be enormously appreciated. Thanks in advance.

tstiglich

Not sure if this will help... https://www.bimmerfest.com/forums/sh....php?t=1072913

When cars sit for a long time, the first thing that comes to mind are mice. Absent a fuse issue, I think that you are going to have to get a multimeter out, check for power, ground, etc. After that, check continuity of the signal that triggers each coil. Doesn't each bank have their own ground cables? Seem to remember two when I changed my valve cover gasket.