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What is the root of this BMW design flaw in all 3,5,7 series BMWtrunk wiring looms?

Discussion in 'Electronic Repair' started by Arthur, Mar 14, 2013.

  1. I would like to acquire some fine-strand wire but I do not have any
    old Fluke leads. Do you know where I can buy some? Thank you in
    advance for any help.
  2. jim beam

    jim beam Guest

    he can only afford to destroy old fluke leads because he didn't buy
    them, his employer did. normal mortals buy high-flex silicone wire from
    electronics stores or online. plenty of people sell short lengths on ebay.
  3. Guest

    As long as it doesn't fail during the warranty period they don't care.

    Is this poor grade wire mandated by regulations?

  4. Charlie+

    Charlie+ Guest

    underneath my scribble :

    Interesting post Jim - do you have any approx. info on milage brackets
    on failures for transmission and other major cost BMW components? C+
  5. Nate Nagel

    Nate Nagel Guest

    You've never had an old British car, have you?

  6. Nate Nagel

    Nate Nagel Guest

    You're probably expecting me to argue with you, but I'm not going to. I
    admit to being one of those people to whom the three most important
    things about a car are power, handling, and braking - so I like BMWs.
    (although the stock brake pads suck unless you like refinishing your
    wheels every couple years.) Other people don't care quite so much and
    consider "adequate" handling to be acceptable; for them, a BMW is just
    too much of a PITA to run so they buy something else. (although current
    ride hasn't cost me anything but maintenance and an oil filter housing
    gasket - knock on wood.)

    And if you want to talk about shite window regulators - I actually had
    an A4 chassis GTI for a while. Yes, the one with the plastic doodad
    that was guaranteed to break. I was understanding when I read that
    their supplier had deviated from the spec, but was angry when the
    dealership said that VWoA wouldn't let them fix both windows when I
    brought it in for the first one... bastards... but I digress...

  7. Nate Nagel

    Nate Nagel Guest

    300 HP from a 3.0 liter six - and likely as much tuning potential as the
    vaunted Toyota Supra - is pretty phenomenal in my book.
    I would never advise anyone to buy a German car with an automatic
    transmission. (and you know that BMW don't actually make the
    transmissions correct? at least in the E9x 3-series I think the 325
    autos are made by GM and the 330/335 autos are ZF-built.) Some things
    never change, the E28 5-series would destroy its automatic if you let it
    engage a driving gear, then shifted back to neutral, then revved the
    engine. (also a ZF box IIRC.) There's an easy solution to that problem
    though; learn to drive a 3-pedal car, or if you want a luxury car that
    your mom will enjoy driving, buy something other than a BMW. (although
    actually my own mom would still probably enjoy driving a BMW, as both
    her GTI and Miata are stickshifts.)

    And as for "planned obsolescence" - you don't think that Ford, GM, and
    Chrysler don't deliberately revise overengineered parts?

    Technically, you are correct, but in practice - it works phenomenally
    well. (and actually the rear suspension is a multi-link with shocks,
    not a strut type suspension.)
    Again, it may be cheap, but it works.

    Would you call a '67 Corvette with a 427/4-speed "junk" because it is
    not technologically advanced? I guarantee you it's still fast by modern
    standards, and fun to drive - and that, at the end of the day, is what
    matters, not whether a particular component is the most expensive,
    theoretically elegant part possible or not.
    Hmm, I see more older Bimmers on the road than I do GM, Ford, etc. (I
    still see a surprisingly large number of E36 3-series and occasionally
    even older ones - I actually saw a 2002 on Thursday - probably the only
    manufacturers that I see *more* 80's era cars still running around would
    be Honda, Toyota, and/or VW and one would ASSume that that's because
    they sold more of them.

  8. Nate Nagel

    Nate Nagel Guest

    Yes. This is the point that JB doesn't seem to get, nor does he seem
    capable of understanding *why* it makes you smile.
    Quite true, and my impression is that German cars are actually better
    than either US or Japanese cars in this respect (as in, if maintained
    they will actually last *longer.*) I don't know if that is true of the
    ones being currently made, but it certainly was 20 years ago.

  9. jim beam

    jim beam Guest

    yeah, after i've replaced every single component three times over,
    including all the stuff that should never break or wear out, the car
    works just great!

    *) I don't know if that is true of the
    there are plenty of 30+ year old bmw's out there. and plenty of 0-10
    yo's. but almost nothing in between. that is by design. see above.
  10. jim beam

    jim beam Guest

    please don't top post, just snip.

    this was back in the 80's and my prof was saying target was 100-120k
    miles. that's not to say it's current target, but i know several bmw
    owners who have had sudden failures at the low end of that range.

    his job wasn't to just fix it for a certain mileage though, it was to
    solve the math on design life so a given target could be achieved. [it
    was a function of the cog tooth root tip radius.] with that solution,
    any mileage could be chosen. modern atomic-scale finite element
    analysis and cnc cutting tools have probably refined his model
    considerably since then.
  11. jim beam

    jim beam Guest

    that's only 100hp/liter. honda routinely had production vehicles at
    120. non-turbo.

    uh, you know that bmw /spec/ their transmission to their contractor,

    nate nate nate, when will you ever learn to read? i specifically stated
    that bmw's /method/ was pioneering but you didn't read that.

    everybody else has been having their crap /wear out/ since the 50's and
    customers hate it. bmw's "genius" was sudden failure that took the
    customer unawares, /and/ presented them with a huge bill that makes the
    majority give up on the vehicle and buy a new one.

    we'll come to fronts in a moment, but did you not read what i said about
    rears??? [rhetorical]

    yeah, a wheel barrow works. particularly when you have tires 30% wider
    than a comparable vehicle that has camber control.

    macpherson is garbage. by definition. go out to any parking lot and
    look at the inside tire of any macpherson vehicle parked with steering
    angled. look at the camber. look at the percentage of tire left on the
    pavement. /that/ is a fundamental problem that can't be solved.

    macpherson is adequate for the straight-ahead and delightfully cheap for
    manufacturers. and that's where the story ends.

    driveling excuses.

    again, you can't read. you see OLD bmw's and you see modern bmw's, but
    you see nothing in between. the old stuff was that brief period when
    they had the engineering right but bmw's financials were in the crapper.
    then in came the mba's, so their engineering focus changed. the
    results are right there on the road in front of you every single day.
  12. Nate Nagel

    Nate Nagel Guest

    That's also stock. A simple flash tune (e.g. Cobb) or piggyback (BMS
    JuiceBox) can get you to 350-375 easily; more with a larger intercooler
    and freer-flowing cats/downpipes. Tony Vargas just dynoed a car on 91
    octane pump gas with "full bolt ons" (generally, that means intake,
    exhaust, and intercooler and possibly a larger oil cooler as well) and a
    set of larger turbos but no internal engine work at 575 wheel HP. That
    sure sounds "phenomenal" to me, and reminiscent of what was being done
    with Supras 10 years ago or so - and keep in mind that tuners have only
    had since 2007 to work on the N54 engine. I suspect that there's more
    to be had (and in fact there are people getting more power out of them
    using methanol injection.)

    I'm sure that BMW knows that there is more potential in that engine but
    they likely don't want the x35is a) competing with the M-cars or b)
    making so much power that they start to have internal engine part
    warranty claims at an unacceptable rate. (because, let's be honest, the
    types of people that buy 500+ HP cars tend to want to use that power on
    a regular basis.)
    Of course, but my point is, that just like headlamps, German mfgrs. seem
    to punish Americans by making their automatics as shitty as possible.
    Stick with stickshift or DSG and you'll be fine. I'm in no way excusing
    the German slushboxes, but their shittiness has not been a secret for
    the last 30+ years.
    You just perfectly described why I drive German cars and *not* Hondas.
    Actually BMW tire sizes are pretty narrow comparatively, 225s on the
    front of a vehicle that curbs around 3400? And that's the M-sport
    package. BMW's tire choices are a good example of one of the instances
    where they have made questionable choices however; the Bridgestone
    run-flats do appear to have been made from actual rocks, without
    actually providing superior tread life.

    Another thing you're not considering is that a strut-type front
    suspension allows room for things like big v-engines in the front of the
    car (remember, the current M3 uses a 4.7 liter overhead cam V-8,) and is
    simpler and may very well weigh less than a comparable SLA design.
    these are all things that must be considered when you're looking at a
    car designed for performance first.

    Don't get me wrong, I'm not slagging Honda for using a SLA suspension -
    far from it - but there are several ways to peel a feline. Honda chose
    one way and makes some very nice handling cars (albeit FWD.) BMW and
    Porsche chose another and also make some very nice handling cars (but
    you can criticize Porsche for sticking with hanging the big heavy bits
    out behind the rear axle, but I suspect that that is in large part due
    to the Porsche faithful not accepting anything else - look at the
    relative failure of the 928 for example - just like we probably won't
    see a Harley-Davidson with anything other than a v-twin in our lifetimes.)
    Hmm. Doesn't seem to hurt any of the top competitors in DTM, BTCC, etc.
    etc. etc. How far are the wheels generally turned in high-G cornering
    maneuvers, anyway? And if you'd ever owned a Bimmer you would know that
    any tire wear problems generally experienced are NOT in the front but in
    the rear, which has an "acceptable" suspension design according to you
    but since BMW's alignment specs have aggressive camber for better
    handling the rears tend to wear the snot out of the insides of the tires
    when the car is driven non-aggressively.

    Finally, if you hate struts so much, why are you constantly slagging the
    Germans, who nobody can deny build beautiful handling cars (and I have
    never driven a car that had as nice steering feel as my old E28 chassis
    535i, I suppose that that is unacceptable though because it used a
    recirc ball steering box which is "outdated" compared to modern R&P?)
    and yet I haven't yet seen you criticize Ford for the execrable
    Twin-I-Beam front end which was unmitigated garbage and arguably
    inferior to a simple straight axle, and was used pretty much unchanged
    save for a swap from kingpins to ball joints (a step backward, IMHO)
    through the mid-late 90's!
    It's not an excuse, customers don't care about such things generally.
    What they do care about is handling and ride. If it is provided by
    means of transverse leaf springs and using the driveshafts as suspension
    links, nobody gives a crap so long as it works well.

    I suppose given the choice between, say, a BMW E30 M3 and a SLA Honda
    Civic, in similar condition, you would pick the Civic because it has a
    more sophisticated suspension design, EVEN THOUGH THE BIMMER IS BETTER
    IN EVERY RESPECT when it comes to what matters to the driver?

    Did you miss the bit where the BMW 3-series has made C&D's 10 best list
    for over 20 consecutive years now? And also the bit where the new
    Accord made this year's list as well, *despite* having the struts that
    you hate so much?
    Where I live Bimmers seem to be one of the most popular cars (along with
    Toyota Camrys and various SUVs,) and I see a whole range of them on the
    road. The very early 3-series cars seem to have mostly disappeared, as
    well as most of the cars that predate the 3/5/6/7/8xx naming convention,
    but then again, I did see another 2002 coupe while out and about this
    morning. If you're looking for any particular design of 3-series
    however, save for the E30, you're likely to spot one within 10 minutes
    or so simply by driving around and looking. I probably see more E46 and
    E36 than I do E9x or F30s.

  13. jim beam

    jim beam Guest

    dude, the 120 is stock. your 100 is stock. last i checked, 120 > 100.
    your math may be different, but that's not my problem.

    that's still only 125.

    intercooler means turbo. if you're only getting 125 turbo, you're not
    very good at tuning a vehicle.

    so freakin' what? there are turbo integras with more output than that.
    and that's only a 1.8l 4-banger.

    you're clearly in self-justification mode and incapable of receiving any
    incoming information.

    ??? why don't /you/ get one? you bought a bmw because you want a
    "powerful" car, right?

    that wasn't your point before.

    um, actually, dsg has been highly problematic. and modern bmw sticks
    aren't exactly champion either.

    it's not a "slushbox", it's an "automatic transmission".

    because you like cars where you're obligated to take big ticket
    expenditure up the ass??? wow, you're even more retardeder than i thought.

    weight is not a factor in tire size. bmw use big tires because it's the
    cheap way to compensate for otherwise having less rubber on the road
    with cheapo macpherson strut.

    wow, two red herrings in one paragraph - you surpass your usual standards!

    i'm sorry, didn't the original pony cars have have v8's and wishbones?
    doesn't the corvette have a v8 and wishbones? oh, wait, you were
    talking out of your ass - no problem.

    all you're saying is that you'll wriggle and squirm for any excuse to
    justify you poor choice.

    you're simply incapable of paying any attention. i don't know how many
    times i've said it before, but apparently i need to say it again - rear
    suspension is important because it's subject to higher lateral force
    given the shorter radius for the same angular velocity as the front.
    /that/ is why rears wear. oh, and they're driving wheels of course -
    can't forget that!

    then you've never driven a nice car if that's your pinnacle!

    you're putting false words in my mouth, then bullshitting about what
    i've never said. that's retarded.

    generally??? could you be any more worthlessly vague??? rolled in with
    your driveling excuses of course...

    no they don't or they'd all be driving miatas, old civics, wishbone
    audi's, etc.

    "works well"??? if i'm used to driving a leaf-sprung solid axle truck,
    am i qualified to say that a bmw drives well? how about if i drive an

    am i not a driver? what matters to me, and all the other touring car
    class champs that drive these civic's, crx's and miata's for that
    matter, is that the freakin' thing works better than the macpherson
    garbage out there.

    car and driver???? ygtbfsm.

    are you for real? did you not read what i said? or do you simply not
    understand it? [rhetorical] you're a total waste of electrons.
  14. Bimmer Owner

    Bimmer Owner Guest

    This isn't an 'argument'; it's merely a discussion.
    Everything you said and everything I said was true.
    The E39 that I own handles those three with aplomb!
    The stock front pads are Jurid, with the rears being Textar,
    both with an FF friction & fade coefficient. They work well
    enough, although Akebono GG friction ratings are often used
    as replacement.

    I use the Axxis/PBR FF pads, which dust the same color as the
    wheels, so you don't see the unsightly darker-colored dust
    of the stock Jurid pads.
    The OFH often leaks on the BMW M54 engine; but luckily it's an
    inexpensive part, albeit a bit of a pain to DIY.

    Overall, I think we're in agreement, so there's really no need
    for any argument. One thing about bimmer owners, they KNOW their
  15. Scott Dorsey

    Scott Dorsey Guest

    I have seen a lot of cars over the years, and I have never, ever seen one
    that used anything approaching quality wire.

    And that begins with the '72 Datsun I had, where all of the insulation turned
    to goo and every foot of wire in the body had to be pulled out and replaced.

    Just take a look at what goes into airplanes vs. what goes into cars and
    you'll be staggered.
  16. jim beam

    jim beam Guest

    you're spoiled if you work on aero-spec stuff.

    car quality goes in cycles - for some manufacturers anyway. in the late
    80's, hondas used a higher grade under the hood - fine wire high count
    high temp high flex [though not silicone], and it's remarkably reliable.
    in the mid 90's they changed to lower flex, smaller cross-section,
    lower count, much more akin to the wire used in the rest of the vehicle
    - it still just about hangs in there, though i doubt it's million mile
    material. i'm pretty sure copper prices had a big influence on this.

    planes cost a /lot/ more!
  17. jim beam

    jim beam Guest

    ??? dude, brake dust is /two/ components:

    1. pad.
    2. disk.

    if your wheels aren't being stained, it's because #2 is not present, or
    at least, not to the extent that "bmw spec" [high silica] pads have.

    i don't understand this equation - y'all are starry eyed about something
    that is completely unreliable /and/ expensive to maintain. sure, it's
    better than a buick, but really?

    if you like fixing stuff and are serious about rwd's with handling,
    race-prep a miata. if you want something that handles from new, buy an

    don't pay bmw's "advertising beats engineering" tax.
  18. Scott Dorsey

    Scott Dorsey Guest

    Did they tin it? The lack of tinning is one of the things that annoys me
    about many of the cars of that era.

    Silicone is actually a problem for cars because if you nick the insulation
    the cut will propagate until it becomes a break.
    It wasn't failing enough, so they had to downgrade it.
  19. jim beam

    jim beam Guest

    no, it's not tinned.

    there are two schools of thought on that. on the one hand, surface
    oxidation resistance is a good thing. on the other, there may be a
    problem with tin in fatigue environments. i don't know this for sure,
    so if you know someone at work who does, it would be good to check - but
    tin has a weird deformation mechanism called "twinning" which changes
    the surface of the metal where it's occurred. given that almost all
    fatigue initiates at a surface, that /might/ be a fatigue initiator.
    how much it might be worse than oxidation, i can't say, but i know a lot
    of mil spec wire is silver plated, not tin, so i think it might not be
    simple cheapness preventing its use.

    indeed, but that's not unique to silicone - many elastomers have the
    same problem.

    maybe. it was was bullet proof - never failed unless abused.
  20. Nate Nagel

    Nate Nagel Guest

    Streetable and civilized? Stock bottom end? I doubt it.
    You're missing the point. There are a few engines that the basic block
    and heads can support massive HP/tuning. The N54 is one of them. So is
    the old Supra engine. That is a Good Thing, if you're a car guy.
    Um, I did! Couldn't be happier with it, either.
    The current 6-speed is a little notchy when cold, but it's also rated
    for quite a bit more torque than your Honda boxes. Certainly not
    anything horribly objectionable.
    potato, potato.
    You do realize that you don't have to buy new, right?

    I paid less for my current ride than my friend did for his similarly
    equipped but FWD and automatic Camry. Make depreciation work for you.
    Clearly you didn't read what I wrote.

    Or are you going to argue that 225's are "big tires"?

    They're also nowhere near as tightly packaged as a 3-series. But like I
    said, there are definitely advantages to a SLA suspension and I'm not
    going to argue that with you. I'm just saying that when you're dealing
    with high spring rates and low travel that struts are not the
    unmitigated evil that you make them out to be.

    I don't need to justify my choices, I'm not the one going on the forums
    slagging well-known manufacturers of performance cars to make myself
    feel better about driving an old Honda.
    Wait, what?
    You've clearly never driven an E28 then.
    I'm just saying, you seem to have a habit of latching on to engineering
    principles and badmouthing designs that you see to be "incorrect"
    without any actual real world experience with them. As evidenced by
    your comments about the E28 above.
    Miatas are great! I'd pass on the Civic because FWD and Audi because of
    the maintenance/repair nightmares. (and Audi weight distribution is a
    little questionable as well - why hang the engine so far out in front of
    the front axle?)
    "works well" = achieves its design objectives.

    If you recall, the original Corvette was supposed to be an American
    alternative to the small European sports cars that were beginning to be
    popular in the US. Given that it sold reasonably well, and was also
    competitive in sports car racing (at least 57-on) I would say that it
    met those objectives.
    But clearly that's not an open and shut case, otherwise a CRX would beat
    an M3 in a race every time which obviously doesn't happen.
    Well show me one authority other than yourself that says that BMW
    doesn't make good handling cars.
    Yes, apparently struts, while technically not as elegant, can be made to
    work well. Glad you finally are starting to realize that!
    I read what you wrote, but it didn't make sense, because you're delusional.

    The E46 and E36 fall into the year ranges that you claim are garbage and
    you "see nothing." I see them driving around, presumably driven by
    happy owners, every day. They haven't disappeared in any sense of the word.

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