Hi all

I have a 2008 UK N53 325i with 48k, symptoms are

extended crank of 3-6 seconds, but always fires after being left overnight or for a few hours,
occasionally and almost imperceptible stutter/misfire, clears after changing from 1st to 2nd gear on first start of the day.

I've had plugs pulled after leaving overnight and no evidence of fuel on them.

No classic symptoms of bad pumps or injectors once driving, no drop in performance.

As they were required had NGK plugs and Bosch coils fitted in last 6 months.

Garage has said there is a 2AAF code, never had EML.

The low pressure side will sit at 5 bar and hold it.

The high side operates at 200bar, drops to 50 shortly after turning off but will then further drop to 5 bar overnight or having been left for a few hours.

Turning off and on creates no extended crank, fires on the button, hot or cold.

Any guidance where to go next would be appreciated.

Thanks