Did you happen to use a little dielectric grease on the coils? I made that "mistake" recently on my wife's E83/N52 and had several brand new coils/plugs having misfires. After a few re-seats, I got it down to only one specific coil misfiring. I had to clean out the grease and re-treat the inner boot with baby powder as they come from the factory (per TIS). Haven't had an issue since.

AM.

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E70 2010 3.0 M57 AT Titanium Silver with Black Leather
E53 2004 3.0 M54 AT Toledo Blue with Gray Leather
E83 2008 3.0 N52 AT Silver Gray Metallic with Black Vinyl
E46 1999 2.8 M52TU 5MT Black with Tan Leather 250K+ miles (Sold, but not forgotten)