Results 1 to 3 of 3

Thread: Cruise Control & Braking at high speed

  1. #1
    Join Date
    Aug 2018
    Location
    Minneapolis, MN
    Posts
    1
    My Cars
    F10 and F30

    Cruise Control & Braking at high speed

    I apologize if my Google-fu is inadequate and information already exists. I can’t find it though so here goes.

    2012 550i xDrive, auto.

    Everything is pretty much on fleek with my car, it does have this quirk though. Cruise control at 70 or so MPH+ results in this infrequent braking phenomena. The problem is prominent when going uphill making me think it is somehow related to load. I haven’t tried it with the cruise set to 80, 90, more... mostly because it becomes very illegal. My presumption though is that cruising at 90 I’d find the problem to be as apparent as it is at 70 with the uphill component. Without cruise set, the problem doesn’t exist.

    The phenomena itself is the car doing brake application. The back end will drop, the real-time MPG goes from 30+ to ~5, and you can simply feel the car drag. The big v8 maintains speed, but you can tell it’s fighting brakes. The phenomena lasts 3-5 seconds then goes away for... awhile. It might occur as frequently as every 20 seconds or so, or as infrequently as never. Seems to be pretty dependent on engine load with a higher load resulting in more frequent occurrences.

    Im sure it has the auto brake drying stuff, but this phenomenon occurs in bone dry weather. The brakes are healthy and seem to work well. Where should I look? Long trip coming up and hoping I can rely on my cruise.

    Thanks

  2. #2
    Join Date
    Jun 2008
    Location
    Dallas, Texas
    Posts
    540
    My Cars
    '14 550/M, '03 540/M
    that's not normal. sounds like a bad sensor somewhere.

  3. #3
    Join Date
    Jan 2007
    Location
    .
    Posts
    7,708
    My Cars
    .
    That's one complaint I've never heard of. First step would be a proper diagnosis scan by a competent BMW specialist that will communicate and scan ALL the control units, not just the DME.
    ASE and BMW Master Certified Technician

Similar Threads

  1. wheel wobble when braking at high speed please help!!!
    By e361995320 in forum 1991 - 1999 (E36)
    Replies: 10
    Last Post: 08-16-2008, 12:54 PM
  2. MY sterring wheels shakes when i press on the brakes at high speeds
    By kpipalldaway2 in forum 1992 - 1999 M3 (E36)
    Replies: 41
    Last Post: 12-05-2007, 06:30 PM
  3. braking at high speeds
    By kronik323racer in forum 1991 - 1999 (E36)
    Replies: 5
    Last Post: 11-29-2006, 11:43 AM
  4. Steering shudders when braking at high speeds
    By blizzard in forum 1991 - 1999 (E36)
    Replies: 11
    Last Post: 06-14-2006, 02:51 AM
  5. braking at high speed.
    By greenfrog1967 in forum 1996 - 2003 (E39)
    Replies: 6
    Last Post: 04-06-2004, 10:39 AM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •