Possible fault causes
- Dynamic driving style when oil level is near minimum (oil foaming)
- Engine oil pressure too high or too low
- Fuel injector faulty or borderline
(opens too late/not long enough/not enough or leaking)
- Bar ignition module faulty
- Leak in intake-air distributor
- Insufficient compression
(e.g. cylinder liner damaged, valve seat ring faulty...)
- Valve lifter faulty
(Intake valve has not switched to the other lift or has not switched quickly enough)