[HPIA4v2]

Originally Posted by hookandpull

Take it back to the dealer and tell them they did a shit job

No it wasn't my car, "myAddiction" posted before-after pictures on walnut-blasting by dealer. almost like no diff. That's why I am not sure I am going to dealer.

The problem is I am not super knowledgeable on engine but I belive the tech needs to open the intake, crank the cam-shaft by hand to close the intake valves, blast them, move to next set of valves etc (on all 6-cylinders), replace the gasket and put the intake back.
I don't want an amateur forget to close the other valve while blasting adjacent ones, then you may have engine lock from walnut dust inside that opened cylinder, can you spell "NEW ENGINE".

I called indy shops who specializing BMW and none ever heard walnut blasting on intake valves