X5 E53 found my vacuum leak
 

Symptom: CEL for a variety of issues:
Misfire on all 6 cylinders
Lean on bank 1 and 2

Tested:
Fuel pressure tested fine on rail
Search for vacuum leaks...

Spraying cleaner on this part revealed the leak. You can hear the idle increase when I spray near the back of the unit (closer to firewall):

I assume this is unit is not supposed to leak air.

Furthermore, when I removed it, I found the "flap" to be loose on one end. Not sure if this is expected or not.


This part number 11617544805 known as the "adjuster unit", over $200. I assume I need to order a new one.

https://www.realoem.com/bmw/photos/11617544805

If the pin is still there and the flap is still working, you can scrape off the o-ring that seals it to the intake manifold and replace it with a square cut o-ring. Don't remember the size of the square-cut O-ring but I believe some paintball gun uses the same square-cut O-ring.

None of the videos are working. Also, you mention that one end is loose, that's not a good sign especially if you are missing the pin. I wouldn't be driving the X until you find that pin. That pin can cause a lot of damage to the valves and head.

You can usually repair DISA with a kit. I fixed my wife's with 20¢ of hardware. Search for awr-fix in title.

Definitely check for that pin.

Pin is there, but greatly worn. Outer pin is in place. Inner pin is there just very worn allowing the flap to move about, but not out of unit)

Not sure why videos aren't working. You can see the video what I'm talking about.

Attachment 80214

You can seal DISA radially also. I use special Teflon tape that changes color under pressure so a couple test fits will determine if I have enough.

The starting fluid test is good to find vacuum leaks but I've heard best to use propane (won't drip into places that can cause a problem). Also, watch your O2 sensor reading real-time and you get a much more sensitive feedback vs. listen for RPM.

AWR-fix: repair DISA for 20¢
https://r.tapatalk.com/shareLink/top...ink_source=app

You can buy a repair kit on eBay for under $20.00n bucks or a new aftermarket DISA valve for Under $60 bucks.

Me, I would go to a Pick N Pull and buy a Genuine BMW part for under $10.00

Read my repair thread. Was 20 min. 20 ¢ repair