pcy

Correct.

There are 2 DISA valves. Part #2 in the link Dan posted is relatively easy to access and replace if necessary. Part #3 replacement requires intake manifold to be unbolted.

Interestingly enough, I replaced that inner DISA (part #3) yesterday evening on my '06 530i because I have had that error for some time. I replaced outer DISA (part #2) almost an year ago.
Each of those DISA valves cost around $250 at BMWmercedesparts dot com.

twh

When you replaced them did you notice any cracks?

pcy

My understanding is that the flaps on DISA valves are supposed to be in closed position [when you remove from manifold] and you shouldn't be able to move that flap.

The flap on the outer DISA (part #2) was in open position and I was able to move that flap. Hence, I know that DISA valve needed to be replaced. Other than that I didn't really notice any other symptoms [or errors on INPA]. I suppose the shaft on that flap will eventually disintegrate and parts get sucked in to the intake.

For the inner DISA (part #3), I have seen error (on INPA) corresponding to part #3. When I removed it from intake manifold, the flap was in open position; however, I wasn't able to move the flap. The flap on new DISA was in closed position. So, my guess is that the flap is stuck in open position.

I still have both of the old DISA valves; I didn't throw them away.

E60I

Hi Pcy,

According to the thread below, part #2 should be in open, locked position.
http://www.realoem.com/bmw/showparts...56&hg=11&fg=40

For a minute, I thought I might have found the solution to my mysterious cylinder #4 misfire problem. :-(

I totally forgot to connect the electrical plug back on the outer DISA (part #2) and drove the car for about 50 miles yesterday on the freeway. The change in power (if there was any changes) was hardly noticeable. I hope I didn't damage anything...