|
|
06-28-2022, 10:56 AM | #1 |
Lieutenant
84
Rep 459
Posts |
Limp mode triggered by braking system?
My car went into limp mode (maximum 2k revs, really sluggish throttle response and 1100 idle speed) twice in the last few days, each time within a mile from cold start.
The iDrive displayed an amber engine management warning light and said that driving moderately was OK but I should take it to a dealer (obviously...). I tried charging the battery for 48 hours between incident 1 and 2. BMW Assist tech guy came to my home today, and read the limp mode messages from the OBD, but the car started and ran (for about 4 miles) without problem. He did say that the brake vacuum system (pump, sensor or seals) was indicating a fault however (and the pedal did feel a bit "soft"). I am taking it into the dealer tomorrow for repair. Just wondering if anyone else has experienced this?
__________________
|
06-28-2022, 12:15 PM | #2 |
Major
1606
Rep 1,128
Posts
Drives: 2009 E92 M3 Dakar Yellow II
Join Date: Oct 2021
Location: Edmonds, WA
|
There is a pressure sensor under the brake fluid reservoir that can go bad if somebody spills brake fluid on it during a service.
|
06-28-2022, 03:07 PM | #4 | |
First Lieutenant
135
Rep 372
Posts |
Quote:
I experienced the same issues when I had my brake fluid flushed and the indy shop haphazardly overfilled the reservoir and fluid runoff malfunctioned the brake fluid reservoir. You should hear your a whining noise coming from the footwell. The pump staying on longer than it should. I was able to prove my case and the shop remedied the issue. At first they wanted me to pay to address the issue. |
|
Appreciate
0
|
06-28-2022, 11:28 PM | #5 | ||
Lord Scrip
1823
Rep 3,018
Posts
Drives: 2011 M3 Coupe
Join Date: Jan 2012
Location: LA,Ca
|
Quote:
__________________
|
||
Appreciate
1
DrFerry6731.50 |
06-29-2022, 07:20 PM | #6 |
BimmerPost Supporting Vendor
3769
Rep 2,912
Posts
Drives: 2011 E93 M3
Join Date: Nov 2014
Location: DFW, Texas
|
Somewhat common for this sensor to fail and cause limp mode. Failure is almost all ways due to fluid contamination.
If this sensor is the fault, braking ability is not reduced as vacuum is not reduced, only its data stream to the DME is faulty. iDrive notifications are exceptionally vague, they never identify anything useful. |
Appreciate
2
spammysammich1606.00 DrFerry6731.50 |
06-29-2022, 09:46 PM | #7 | |
Major
1606
Rep 1,128
Posts
Drives: 2009 E92 M3 Dakar Yellow II
Join Date: Oct 2021
Location: Edmonds, WA
|
Quote:
|
|
Appreciate
1
DrFerry6731.50 |
06-30-2022, 06:15 AM | #8 |
Friends don't let friends ESS
3223
Rep 886
Posts
Drives: '11 Lemans Blue 6mt Harrop e90
Join Date: Dec 2020
Location: Camas, WA
iTrader: (0)
Garage List 2011 E90 M3 [9.00]
2003 Porsche 911 Turbo [9.75] 2019 BMW X5 xDrive40i [0.00] 2013 Mercedes E550 ... [0.00] |
Easy DIY - had the same problem in May
Replacing Brake Vacuum Pressure Sensor https://www.m3post.com/forums/showthread.php?t=1338052 |
Appreciate
2
DrFerry6731.50 spammysammich1606.00 |
07-05-2022, 02:14 PM | #9 | |
Lieutenant
84
Rep 459
Posts |
Quote:
Brake fluid change about 6 weeks ago.....by the Main Dealer. I have not heard any excess pump noise, nor noticed the pump running for longer than normal (TBH - I am not sure that I have noticed any pump operating noise anyway). If it is bad work by the dealer, I think I might well be refusing to pay the £100 excess on the warranty claim.
__________________
|
|
Appreciate
1
DrFerry6731.50 |
07-05-2022, 02:20 PM | #10 | |
Lieutenant
84
Rep 459
Posts |
Quote:
Dealer left me a voicemail this morning, stating that it is not a faulty sensor, but there is a vacuum leak, which they are still trying to locate.
__________________
|
|
Appreciate
0
|
Post Reply |
Bookmarks |
|
|