|
|
|
|
||||||||||
| Xoutpost server transfer and maintenance is occurring.... |
| Xoutpost is currently undergoing a planned server migration.... stay tuned for new developments.... sincerely, the management |
 |
|
|
LinkBack | Thread Tools | Display Modes |
|
|
|
#1
06-30-2023, 09:40 PM
|
|||
|
|||
|
Low speed braking
Another week another issue with the X
At low speed the brake pedal goes solid and feels like it has no stopping ability. My understanding is that it’s the brake servo unit (34336760461) Hoping someone can validate this for me and then advise whether I should also change the master cylinder at the same time. Thanks all 
|
|
#2
06-30-2023, 11:14 PM
|
||||
|
||||
|
The vacuum pump is where I'd look. For some reason BMW thought the 8 cylinder engine couldn't make enough vacuum so..... let's just say when mine failed after a 4 hour highway trip that in town traffic made my seat change into a traffic cone
 If you hear a gurgling like water behind the dash it 100% the pump. Sent from my SM-A528B using Tapatalk
__________________
"When the Team Chief said.... You're trapped in a hole with nothing but a goat and a slinky, what do you do? Stubby said, I'm not sure but it won't end well for the goat...." ~(Overheard) Last day, Phase 3, Q Course
|
|
#3
07-01-2023, 06:43 AM
|
|||
|
|||
|
Quote:
I would first check the vacuum pump is producing vacuum and also check the non-return valve on the hose connection. It seems that the valve is not available separately but comes with the hose. https://www.realoem.com/bmw/enUS/sho...diagId=34_1350
__________________
E39 530dA -02 M-Sport Messing metallic E53 X5 3.0dA -06 Sport Stratus grey E70 X5 40d -12 M-Sport Space grey
|
|
#4
06-30-2023, 11:20 PM
|
|||
|
|||
|
Low speed braking
Thanks for the info - sorry this is a total noob question but I had no idea there was a brake vacuum pump on these, where is it located/what does it look like? If I google I’m seeing this thing - which I know I changed the o rings in a few years back when I had it off for the valve stem seal replacement, had no idea it had anything to do with the brake system though
 Sent from my iPhone using Tapatalk
|
|
#5
07-01-2023, 12:38 AM
|
||||
|
||||
|
Here's the part numbers
 Sent from my SM-A528B using Tapatalk
__________________
"When the Team Chief said.... You're trapped in a hole with nothing but a goat and a slinky, what do you do? Stubby said, I'm not sure but it won't end well for the goat...." ~(Overheard) Last day, Phase 3, Q Course
|
|
#6
07-11-2023, 06:28 AM
|
|||
|
|||
|
So I started by replacing the hose and clamps as the hose was rock hard no change, changed the pump unit entirely and still no change. I press the brake, hear a whoosh of air and then the pedal goes hard with no brake force.
Any ideas where I should look next? Thanks Sent from my iPhone using Tapatalk
|
|
#8
07-11-2023, 09:14 AM
|
||||
|
||||
|
If the brake booster "whooshes" air that suggests a vacuum leak in the diaphragm side past the valve associated with the brake.
Run the car to build vacuum, turn off the car and have somebody else press the brake while your are under the hood listening to the brake booster to figure out where the air whoosh is coming from.
__________________
2011 E70 • N55 (me) 2012 E70 • N63 (wife)
|
|
#9
07-16-2023, 07:15 PM
|
|||
|
|||
|
I have these same symptoms. Vac pump pulls and pulses. I do hear a whoosh sound. Does this point to booster?
Thanks!
|
|
#10
07-16-2023, 10:48 PM
|
||||
|
||||
|
Quote:
When do you hear the whoosh? Vac pump pulls air Ina lot of places. I have an internal vacuum leak in my valve cover causing fits.
__________________
2011 E70 • N55 (me) 2012 E70 • N63 (wife)
|
|
| Bookmarks |
|
|
|
|
Hybrid Mode
