Swirl flap damage to my 320d - common?

My BMW 320d, 04 plate, broke down a few weeks ago with a clattering sound. It was towed to the garage. They said that one of the swirl flaps had fallen into the engine. The garage is looking for a replacement engine.

The car has been well looked after and has only done some 75,000 miles. Surely this should not have happened?

Asked on 8 April 2013 by Mr G A Dobson

Answered by Honest John
Quite a common problem with BMW 2.0 litre and 3.0 litre diesels from this period. Standard advice is to remove the flaps and motors and suffer the slight loss in efficiency.
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