[rob_h10]

a friend of mine recently brought his 335i to bmw complaining of surging and loss of power during acceleration..

service dept ended up inspecting the intake manifold and found excessive carbon build up... and the fix?

they "Perform(ed) Walnut Shell Blasting Carbon Cleaning With BMW Special Tool".. supposedly cleaned the intake stem valves to a "mirror-like" finish.. and the best part was this was all covered under warranty!

[blisstik]

How does that tool look like? That's what we all need!

[Jeff@TopGearSolutions]

Surprised they did it under warranty they usually claim it's not covered.

[Tzu]

I posted in another thread a month or two ago, BMW cleaned my valves under warranty, for the same reasons. Walnut shell blasting is very similar to grit blasting but with larger grain diameter.

My dealership did it the old fashioned way though, steam, de-carbonizer and a brush.

I was told that in Canada, BMW got the go-ahead for this repair about 3 months ago, so I'd expect to see this happening much more often at servicing.

[Snertz]

http://www.minitechinfo.com/tsb/atta...ing_Manual.pdf

BMW blaster tool, runs about 1k for one I think. Who here wants to be the guinea pig

[B_davis]

Originally Posted by Snertz

http://www.minitechinfo.com/tsb/atta...ing_Manual.pdf

BMW blaster tool, runs about 1k for one I think. Who here wants to be the guinea pig

As bad as my valves get after 5k miles, I would seriously consider this. I've cleaned my valves 3 times since 45k miles. I am running meth now, I hope this solves my issues.