Got car back and garage report they didnt find the flap or parts of flap, plus no damage internally. So it looks like someone decided to remove the flap at some point!!!! I will now look at either replacing the whole unit or buy the repair kit which flap.

^^If the vaccuum pot is good (you can test it easily) just get the GAS kit and rebuild it for $80

How can you test the pot?

BMW M54 DISA Repair Kit DIY

You probably will have to test using step #11 since you don't have a flapper valve.

However, I'm fairly certain your pot will be good since it rarely goes bad.

Cheers, will take a read. That said, was just searching and flap upgrade kit is around £70 ($100), but can get a brand new DISA unit for an extra £90. So may just go for the new unit.

Somebody bought disa repair kits on this site Repair kit Disa BMW ???
Included is a new vacuum membrane.

http://vanos-bmw.com/images/Disam54-30_small.jpg

^I would rather buy from the original (G.A.S.) and get support if needed. That website looks like a third grader made it.

hmmm ... I see they have a large range of products, including Kit to have m52tu and n52,53,54, which have no G.A.S.

Looks like a eastern european site, might be more convenient to some of our Euro posters than G.A.S. for delivery, support, etc. That may also explain some of the 'English as second language' website grammar.

Just inspected my DISA, everything is fine: flap, pin still in place.

However, as trader4 said, the DISA flap is like a human appendix.
So I am thinking "appendectomy" to prevent future engine damage.

Has anyone here removed the DISA flap + pin? What is the consequence?