Hi all,

Im working on my bmw e53 4.8is. It has misfires, starting at cylinder 5 and progresses to other cylinders, also from bank 1.

Today i heard noise coming from valvetronic motor on bank 2 at idle. It sounds like a bearing is almost at end of live.i took the motor off checked the shaft and bearing play, but didnt feel anything.

So far for misfire if done the following:

-changed all spark plugs
-changed all ignition coils.
-changed CCV valves
-checked MAF sensor.
-changed vacuum pump seals.
Next up, will do a smoke leak test.