z4 coil problem

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z4 coil problem

Postby rachael » Tue 07 Feb, 2006 15:28

Hi, long story sorry! but please get you car checked and let me know if you have a similar problem after such a short time!

I bought my first BMW in Sept 03 – a Z4. Around 6 months later I found a piece of metal on the drive, but thought it had fallen off the bin lorry (a woman’s sense decision!) Then a couple of weeks later found a second similar coiled piece of metal. I asked a neighbor who is an engineer for Vauxhall, and he confirmed they were pieces of the coils suspension spring from a car. We tried to look at the Z4, couldn’t visualize the springs but could feel them, and the thickness of them mistakenly led us to believe they were from another car (not the z4).
I dutifully took the car for its 15000 service, and since the garage didn’t mention a problem felt this was confirmatory to my suspicions that the coils were in tact. I now realize however that a mechanical review is not performed at this service, simply an oil change etc.
At 25,000 after a holiday (so the car had been stood) I felt the car was making an unusual noise. The garage told me it was because of the breaking of these coil springs, which I presumed had recently happened since the car had appeared to drive normally before my holiday. I asked to look at the springs when they were removed, and to my surprise the missing pieces were the same width as the ones I had found on the drive, with the fracture lines appearing the same (to the naked eye at any rate). Also the fractures were well rusted and so realistically had not only just occurred.
I’m now concerned that other Z4 drivers may have had the same problem, and wouldn’t be aware, since the car had no change in drive or handling generally, and the coils are not checked routinely at 1st service. These fractured after only around 6 months of buying the car from new. I don’t live where the roads are really awful. I don’t drive the car “hard”, and most of my drive is motorway to work and back.
The dealership thought I was just being awkward about the fracture, but I feel like it’s unreasonable for them to break after 6 months. Since I now know the coils wouldn’t be checked unless a problem is indicated, or at the service which is likely to be after warranty runs out I wonder if there is anyway of encouraging owners to get it checked ASAP, since I don’t think many Z4 would have reached their 3 year date yet.
Do you think I’m being unrealistic in my expectation of the coils – as my next step is to write to BMW?
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  Z4 roadster 3.0i

Postby greg_ch » Tue 07 Feb, 2006 16:08

Hi Rachael,

Thanks for the heads up. You were right to bring this to the attention of others as the consequences of a set of broken springs are very serious. This is all the more important because many people here drive their Z's very hard.

Unfortunately it's not the first time this issue has surfaced. It's become a 'common' issue on the Z4 I am afraid.

If you want more background take a look at this thread:

http://www.z4um.com/viewtopic.php?t=102 ... ht=springs

Greg
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Good info Greg. Thanks for the link.
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Broken rear springs

Postby Ex330i » Tue 05 Feb, 2008 17:39

I had the bottom one and a half turns of my off side rear spring shoot out across the road yesterday - narrowly missing a pedestrian.

Car is 41 months old but only 24K on the clock. 13 months since I bought it from main stealer. Never tracked, thrashed, overloaded.
The break has some corrosion around it from where it sat in the bottom cup mount, but there is also a small area of yellow in the metal grain - looks like sulphur??- on the outside edge of the fracture

Although outside warranty the stealer agreed to replace the spring and check the other one + the spring mounts all fee of charge.
(I think this was mainly because the number of times they saw my face during the first 3 months, when I had a string of problems, including a complete replacement of the SMG transmission, none of which were sorted first time!)

The service guys actually laughed on hearing about the near miss with the pedestrian - but saw the serious side when I showed them the lump of spring! God knows what this could have caused to traffic behind me if it had fallen out on the motorway!!!

It doesn't end here though! I previously had a 330i which went in for new rear pads at about 60k. The stealer called during the work to say some springs also needed changing - I assumed these may have been on the rear handbrake shoes as the girk said "not expensive". When I collected the car it was an extra £400!! Both rear springs changed although only one broken! (It had passed an MOT 2 months before when they advised rear pads soon!
10 months later they found a spring gone again. but agreed to pay the labour cost.

Funny how they only change one spring when they are paying?!
Last edited by Ex330i on Wed 17 Sep, 2008 12:34, edited 2 times in total.
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  Z4 roadster 3.0i
Location: West Bromwich

Postby Chris Xoe » Tue 05 Feb, 2008 18:12

I had an identical experience on my old 3.0. - Insisted on changing BOTH sides under warranty.

- mention 'negligence' - i.e. if you have an accident now and the second spring is a contributor factor, they had the opportunity to change it but didn't.

... they will change it! :wink:
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  Z4 coupe 3.0si
Location: Worcester

Rear Z4 coil spring

Postby Golfer » Sat 24 May, 2008 09:49

I have just had a spring fail after 12,500 miles on a 2003 vehicle

Has anyone had any joy getting the problem resolved outside of the warranty period.

I am taking it up with BMW and will let you know how I get on

Regards
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  Z4 roadster 3.0i
Location: Bishops Stortford

Postby mjet » Sat 24 May, 2008 10:44

Just checked my 03 with 22k on the clock. The springs are all good :D
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  Z4 roadster 3.0i

Postby Ex330i » Sat 24 May, 2008 18:56

It can be difficult to see anything wrong - it's usually the very last turn where the break occurs and this is hidden by the cup which locates the spring. You need to jack the car up till the spring is fully extended and even then you may not see it without disconnecting the bottom shock mount first to drop the spring out.
My 330i passed an MOT with a broken spring at a main dealer, but they found the spring break a week later when I went in for new rear pads (that were advised in the MOT report). The broken end was well corroded - i.e. had happened a long time before and I don't recall noticing any clanging when the broken bit fell out. So it may even have happened before I bought the car two years earlier!!
There was no mistaking the racket when my Z4 spat one out, but again everything looked normal until the rear shock was bottom mount was taken off and the car jacked up!
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  Z4 roadster 3.0i
Location: West Bromwich

getting this fixed!

Postby Narcolo » Fri 18 Jul, 2008 16:27

Hi all, new here....

I know this is an old old thread but I recently had the same issue while driving. Car is 03 z4 2.5 with 45k miles. Just came out of warranty.

Suspension fell apart on the freeway a couple weeks back, immediately causing the vehicle to bottom out and DESTROYED my REAR DIFFERENTIAL!!! How dangerous is that?! Lost power and just coasted to an off ramp.

http://www.zpost.com/forums/showthread.php?t=154812

Car is sitting at a dealership in Los Angeles. Had a BMW North America factory technician come out and try to do goodwill coverage since the damage out of my pocket would be $3300 usd!!!! This seems like a more common problem then I would have thought. Why hasn't BMW addressed this!?

Has anyone had success dealing with BMW customer relations in this matter? Is it really possible for this suspension failure to take out my rear diff!? They have DENIED any type of support for my situation as if its normal for spring coils to just "break", now im stuck with this POS car!

:head:

ANyone with some insight? please help!
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  Z4 roadster 2.5i
Location: OC

Rear Springs

Postby Ex330i » Sat 19 Jul, 2008 08:52

When I first had this problem on my previous car, a 330i, it was discovered when they were replacing the rear pads. I got charged £300+ for 2 new springs. (Only 1 had broken - bottom half a turn but they insisted you should always change both sides together to retain equal balance.)

The same car failed its MOT 10 months later - same thing, same side. They wanted to charge again. I said NO! - they paid but would only change the broken side.

When it happened on the Z4 at 24k miles - out of warranty - I knew about it as I heard the broken coil shoot out! They did under good will, but after inspecting the nearside and confirming OK only changed one spring!
Last edited by Ex330i on Wed 17 Sep, 2008 12:36, edited 2 times in total.
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  Z4 roadster 3.0i
Location: West Bromwich

Rear Coil Springs

Postby Ex330i » Wed 17 Sep, 2008 12:29

Just been told the Z4 failed its 2nd MOT, at just 28k miles, with yet another broken spring, just 7 months and 4k after they changed the other side and assured me the nearside didn't need changing.

The broken end is very corroded through 3/4 of its thickness, the last 25% is fairly bright from a recent break, but has obviously been almost cracked through for some time!
BMW paying for it again, which is good - no car till they get a spring in stock, which is very bad!!

(Sytner Central B'ham)
<b> http://i183.photobucket.com/albums/x60/ ... 453a-1.jpg
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  Z4 roadster 3.0i
Location: West Bromwich

Postby madbrummie » Thu 02 Jul, 2009 11:07

I've just come across this one too, does anyone know if BMW were replacing them for free outside the warranty period? Read some rumours that they were....

Many Thanks
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  Z4 roadster 2.2i

Postby Ex330i » Thu 02 Jul, 2009 11:48

I had mine replaced free - but they wouldn't replace both sides, saying the other one was OK - but if you pay they insist both should be changed for safety's sake!!!!!!
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  Z4 roadster 3.0i
Location: West Bromwich

Postby MarkR » Thu 02 Jul, 2009 12:07

I had one rear one replaced under extended BMW warranty
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Location: Dunstable

Postby madbrummie » Thu 02 Jul, 2009 12:08

They're having none of it because its out of any kind of warranty... ahh well worth a shot! Thanks gents and lasses....
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  Z4 roadster 2.2i

Postby Ex330i » Thu 02 Jul, 2009 12:15

Mine was well out of warranty - done on "good will". (Sytners) Ask them why one rule for one and one for another!
<b> http://i183.photobucket.com/albums/x60/ ... 453a-1.jpg
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  Z4 roadster 3.0i
Location: West Bromwich

Postby gookah » Thu 02 Jul, 2009 13:55

BMW coils springs are s**t, change them as soon as possible for after market ones. What ever you do, do not replace with overpriced BMW rubbish springs again.
I have had this problem on two E46 coupes, an E36 coupe and a z3, all with the sport suspension. could have had two BMW ones for the zed for £300 or the full set of racelogic ones for £75. I didnt pay the extra for worse quality!
I think they must use the same quality standard for wishbones as well
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  Z3 roadster 2.8

Postby madbrummie » Thu 02 Jul, 2009 14:01

It goes back to them in a couple of months anyway so i'm not all that bothered about that, as long as it lasts until then!! The car is great, but things are tight right now with the recession biting so i need something much cheaper!
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  Z4 roadster 2.2i

Postby Ex330i » Thu 02 Jul, 2009 14:04

I know for a fact that Mercs & Vauxhalls suffer from the same thing - maybe others too. Vauxhall will always replace FOC - and always in pairs too!!

Now I'm not saying this is a factor, but walk round our town down any road with speed bumps and you will nearly always find bits of road spring in the gutters!

It should be easily possible to make road springs that outlast the vehicle - it ain't rocket science.
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http://i183.photobucket.com/albums/x60/ ... N4456s.jpg </b>

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  Z4 roadster 3.0i
Location: West Bromwich

Postby CollyB » Fri 03 Jul, 2009 18:05

Was wondering what actually happens to the car if you're driving it and a spring goes, is it still drivable? So you can at least get it home/ to garage etc etc
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  Z4 roadster 2.2i
Location: Garstang

Postby Ex330i » Fri 03 Jul, 2009 18:33

Most springs break on the very top or bottom turn - the tapered bit that sits in the reatining cup and is very difficult to see. The difference in ride height is not noticeable. (I've had 5 go on two cars!!!)

Unless you heard the broken bit fall out (they tinkle down the road like a old clock chimimg!) then you usually can't even tell you have a broken spring - that's why most only get discovered at MOT time - and only then if they are looked at carefully!
Sometime you may hear a rattle when travelling at moderate speed (30 - 40 mph) over a relatively flat road that just chatters the suspension - particularly while the broken bit is still in there. Otherwise you wouldn't know!

To see th ends of the spring you need to jack the car up and let the suspension drop tp the limit - even then you may not spot the break!

The bottom shock absorber mount has to be undone, so allowing the bottom wishbone to drop enough for the spring to be removed.

If more than a couple of turns break off then there is a risk of the spring falling out when the suspension is extended.
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  Z4 roadster 3.0i
Location: West Bromwich

Postby CollyB » Fri 03 Jul, 2009 18:54

Ah I see, so it doesn't suddenly fall on its backside then.

When mine was in the air during its January MOT the geezer said my springs look "thicker than normal". Maybe they've been replaced already-- touch wood.
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  Z4 roadster 2.2i
Location: Garstang

Postby CollyB » Fri 03 Jul, 2009 18:55

Ah I see, so it doesn't suddenly fall on its backside then.

When mine was in the air during its January MOT the geezer said my springs look "thicker than normal". Maybe they've been replaced already-- touch wood.

Why's this been posted twice? I only submitted it once! Can someone delete please, it looks untidy.
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  Z4 roadster 2.2i
Location: Garstang

Mine Too

Postby sma9 » Mon 07 Dec, 2009 11:56

Just been into my local dealership for an engine fault and they found that my springs were broken too.
Is this a common fault on Z4's?
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Re: Mine Too

Postby Chas C » Mon 07 Dec, 2009 13:16

sma9 wrote:Just been into my local dealership for an engine fault and they found that my springs were broken too.
Is this a common fault on Z4's?


Yes its common - had mine replaced by an independant who told me is was a common problem on a number of cars - seems a manufacturer in 2002-2005 had an issue on material used.
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  Z4 roadster 2.5i
Location: Barton on Sea

Re: z4 coil problem

Postby les » Thu 31 Mar, 2011 20:44

Hi

My 2.5 Z4 Roadster soft top registered in 2007 has only done 24,000 miles, in fact since my 2010 MOT it has only done 2,000miles. At todays MOT the garage informed me my coil spring needed replacement. This I am annoyed at. This is a BMW German engineered car and I would not expect to be changing a coil spring after 24,000miles. From conversations with the local BMW garage this is a common occurrence with a Z4, Surely if this is so, why haven't BMW called in all Z4 and replaced faulty coil springs or improved the quality of the coil springs. From reading your pages this has been a probllem with Z4s from day one.

Les R
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Location: Liverpool

Postby gookah » Thu 31 Mar, 2011 21:06

get used to it! BMW don't fit coil springs that last. They are coated in plastic. salt/grit gets onto the bottom mount and the movement of the spring means the grit pierces the coating. Water then gets into it and rusts it away. design is crap. Change for aftermarket otherwise you will just have the problem again.

What you have to remember though, is this is usually picked up on MOT's or services, so the fact that it waits until then means it causes no noticeable problems to handling in between. dont fret about it just change them when it happens.
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Coil Springs

Postby Ex330i » Fri 01 Apr, 2011 08:49

It's not just BMWs - local garage says Mercs are about as bad and Vauxhalls. They are a GM dealership and always replace both sides free when they come across it - not like BMW who may replace the broken side free if you're lucky but charge for the other side!
Ive had 3 go, but no trouble since the last two were changed 2 years ago.
<b> http://i183.photobucket.com/albums/x60/ ... 453a-1.jpg
http://i183.photobucket.com/albums/x60/ ... N4456s.jpg </b>

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  Z4 roadster 3.0i
Location: West Bromwich

Rear coil springs

Postby Ex330i » Mon 07 Nov, 2011 15:48

Just to keep up to date - had yet another rear spring fail today - amazingly while in stationary traffic!!
Heard it snap just behind me followed by a telltail ring as thye top section fell into the main spring body - didn't feel any movement, then as I drove off I got the now familiar clanging as the broken bit fell out into the following traffic and bounced along the road.
This will be the third time now - 3 springs in 51K miles just isn't good enough. It will be interesting to see if they want me to pay this time - last two replaced by Sytners free outside normal warranty. I'll keep you posted!
<b> http://i183.photobucket.com/albums/x60/ ... 453a-1.jpg
http://i183.photobucket.com/albums/x60/ ... N4456s.jpg </b>

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  Z4 roadster 3.0i
Location: West Bromwich

Postby gookah » Mon 07 Nov, 2011 18:03

gookah wrote:get used to it! BMW don't fit coil springs that last.


Don't say I didnt tell you.... :D
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Re: z4 coil problem

Postby Guest » Mon 07 Nov, 2011 19:28

les wrote:Hi

Surely if this is so, why haven't BMW called in all Z4 and replaced faulty coil springs or improved the quality of the coil springs. From reading your pages this has been a probllem with Z4s from day one.

Les R


They wont recall if they dont have to, as they then have to publicly record the fact. They are playing the numbers game, it is either a design, a material or material processing issue that did not get captured until the first recorded failure, which would mean 1000's are affected. They will look at the FMEA to see if it is a safety issue or not, and then decide to either recall, service retrofit or fit on failure, the first one obviously will put the supplier out of business, the latter two will be dealt with by warranty claims on the supplier, hence why they fit them free of charge even outside warranty. It is cheaper to do so.

I have worked on numerous potential issues on vehicles, luckily for the suppliers involved they have not led to recalls, but they have either been dealer fix or gate hold and retrofit on site. The last one involved an 800 hour engine test, the engines passed the test and production was released (based on product integrity and application testing) the 800 hours simulated the serviceable life of the engine.

Some suppliers have not been so lucky, just google the Firestone versus Ford issue, where people were alleged to have died due to tyre failure. Vehicles were recalled and the tyre plant was closed due to the issue. I still do not think it is settled.

I can only assume that on review of the facts they consider the product safe, and also the mode of failure as only an annoyance to the customer.

recall check websites below to see what safety recalls and investigations have been recorded on your model year:

http://www.dft.gov.uk/vosa/apps/recalls/default.asp

http://www-odi.nhtsa.dot.gov/tsbs/
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Rear coil springs

Postby Ex330i » Mon 07 Nov, 2011 19:42

To date all of my spring failures - 3 on the Z4 and 3 on a 330i - have involved either the top or bottom final turns where the spring sits in the top or bottom cup. There is virtually no change to the ride height and the main body of the spring is most unlikely to fall out in this condition. (It's still under a degree of compression even if the suspension is fully extended.) So, seems fairly safe - except for the fact that in the last instance the broken part was run over by traffic and could have caused a puncture or serious tyre damage to anyone following - not something you would want to come upon on a motorway - and the previous failure on the Z4 caused two pedestrians in a bus queue to run out of the way of the sharp and quite heavy broken piece as it bounced across the road and footpath at considerable speed. So the risk of injury / accident is significant. So BMW & many other makers that have the same problem with road springs are being negligent here!
God forbid a spring should fail in the middle section at speed and the suspension collapse!!
<b> http://i183.photobucket.com/albums/x60/ ... 453a-1.jpg
http://i183.photobucket.com/albums/x60/ ... N4456s.jpg </b>

<b>Sport Pack, 18" Elipsoids, Carver Sound System, Bi-Xenons, Rear Spoiler, Auto-Dimming Wing Mirrors, Rain Senor wipers, Wind Deflector, SMG Transmission, Electric Seats (memory on drivers side), 3 stage Seat Heating.</b>
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  Z4 roadster 3.0i
Location: West Bromwich

Postby Guest » Mon 07 Nov, 2011 20:05

If you think this scenario is scary, then the one about lorry wheel bolts is even worse, as it involves a wheel travelling at 70 mph on its own. That is why lorry wheels have those plastic arrows on so it is very clear when a bolt is loosening and unwinding!

On Aircraft incl Helicopters The fasteners are always wired to the next in line so that loosening by vibration is counteracted by the direction of the wiring (hopefully)..........

The blades in gas turbines on airliners get hotter than there melting temperature etc..........

I think it needs to be pointed out that the probability of an accident is in reality very very very low, as you have to have the right (or wrong) conditions at the right (or wrong) time, bit like an asteroid hitting the earth (only happened once so far), so lets not panic just yet and abandon our vehicles, all parts have a major factor of safety built into them than is actually required in the application.

Pity washing machines can't be designed the same way!
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