[DrivingPassion]

1. Walnut blasting: I recall my dealer used to try to sell me this but when I asked about it recently, they said they do not have it anymore.
2. Heavier oil: looks like heavier oil evaporate less
3. Does F22 have a PCV feedback loop back into the valves?

What do you guys do?

[aerobod]

Originally Posted by DrivingPassion

1. Walnut blasting: I recall my dealer used to try to sell me this but when I asked about it recently, they said they do not have it anymore.
2. Heavier oil: looks like heavier oil evaporate less
3. Does F22 have a PCV feedback loop back into the valves?

What do you guys do?

Did chemical softening and scrapping with a plastic scrapper at 100,000km on the N54 in the 135i. So far doesn't look like it will be needed in the B58.

Before and after cleaning on the 2010 135i N54:

[DrivingPassion]

Why does the B58 not need this? Is the B58 a hybrid = PFI + DI ?


You dug all the way in there for yours? What kind of chemical cleaning did you use?

[aerobod]

Originally Posted by DrivingPassion

Why does the B58 not need this? Is the B58 a hybrid = PFI + DI ?


You dug all the way in there for yours? What kind of chemical cleaning did you use?

So far there doesn't seem to be cases of higher mileage B58 engines needing valve cleaning, compared with the same time period after launch as the N54. The N55 engines also had less of a problem compared with the N54. Control of blow-by gases seems to be a lot better. Tuned engines may have more of a problem - my tuned N54 suffered more blow-by and oil in the intake than when it wasn't tuned, leading to more intake valve contamination.

Cleaning the N54 by removing the inlet manifold took about 2 hours of assembly/disassembly and 3 hours of cleaning, but leaving the car 2 nights to let the chemicals work overnight on half the valves at a time (ensuring they were shut during the cleaning). Basically used a standard cleaner such as this https://www.canadiantire.ca/en/pdp/c...p.0388077.html with small plastic scrapers, toothbrushes and tooth picks and removed final residue with a shop vac after mopping up the liquid cleaner. Final step was an oil change in case any cleaning chemical had made it's way into the oil.