To meet European emission standards, modern BMW diesel engines have included the use of swirl flaps to increase efficiency at low engine load.
Due to the nature of being a moving part, wear can occur at the pivot and failure is all too common. Should you suffer this, catastrophic engine damage is very possible. Removal of these valves is advisable, especially if you consider your car of higher mileage due to the wear that is likely to have occurred. You will still pass an MOT and there will be no noticeable difference to fuel economy or power.
The inlet manifold is removed
Here is a swirl flap still installed (also leaking a little oil)
The swirl flap and seal are then removed and a blanking plate inserted in its place along with new seals.
This is repeated on every inlet port. The engine is then rebuilt.
Get in touch to prevent terminal engine damage!