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Discussion Starter #1
Guys

As you might be aware, my 540iLE came with the full 1995 M5 suspension, including EDCIII.

The rear is feeling very hard and unpliable, bouncy even. There is no noticeable change in this feeling - even when I switch between S and P. In any other car, I would conclude that the struts are shot.

Visually they appear to be fine with no sign of leakage (they have done around 105,000kms, or 60,000miles) and there are no check control warnings.

Is it likely that the struts are not working (and require horrendously expensive replacement), or could some other fault explain the problem?

Thanks in advance.

Cheers
 

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It sounds like they are OK, but may need resetting. It sounds like the EDC has defaulted to the medium setting. This is a fairly inexpensive job circa £30 at your local BMW dealer.

I was told you can; and I have done a reset by disconnecting the negative lead from the battery and leaving disconnected for approximately an hour. This has effectively reset your ECUs, both engine management and suspension.

I believe if there was any type of failure with the rear EDC that it would show itself as a 'leak'. I had one of the pipes fail; and let me tell you the CHF fluid comes out at circa 2000psi and you know all about it, loss of power steering etc.

Worth a check of your fluid resovoir though?



M540i LE said:
Guys

As you might be aware, my 540iLE came with the full 1995 M5 suspension, including EDCIII.

The rear is feeling very hard and unpliable, bouncy even. There is no noticeable change in this feeling - even when I switch between S and P. In any other car, I would conclude that the struts are shot.

Visually they appear to be fine with no sign of leakage (they have done around 105,000kms, or 60,000miles) and there are no check control warnings.

Is it likely that the struts are not working (and require horrendously expensive replacement), or could some other fault explain the problem?

Thanks in advance.

Cheers
 

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M540i LE said:
Guys

As you might be aware, my 540iLE came with the full 1995 M5 suspension, including EDCIII.

The rear is feeling very hard and unpliable, bouncy even. There is no noticeable change in this feeling - even when I switch between S and P. In any other car, I would conclude that the struts are shot.

Visually they appear to be fine with no sign of leakage (they have done around 105,000kms, or 60,000miles) and there are no check control warnings.

Is it likely that the struts are not working (and require horrendously expensive replacement), or could some other fault explain the problem?

Thanks in advance.

Are they leaking out of the top of the damper.
This is the character failure.
As the struts start to fail, they start to patter as vertical motion excites the damper. the solenoids within the damper are still being actuated to control the flow of oil betwen the damper chambers & therefore the damper chamber pressures.
The seals at the top of the damper are the culprits for sure.
They start to breathe or vent under the high pressure which is constantly being modulated by the solenoids opening & closing but as the pressure is being vented it cannot stabilse the damper movement in either jounce or rebound condition.

If you are not getting the pattering or cannot see the telltale oil seepage on top of or down the damper leg then start to look at the self levelling system
for obvious leaks.

EDC fault check if not already undertaken may also indicate issues.

Hope this might help a little.

Regards
Farrell
 

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If it's bouncy I would definitivelyt check the accumulators, and while you're at it check all hoses (there are five: one going to each of the schocks and three to and from the regulating valve) especially the high pressure intake one.
Mine were responsible for that.
Jaime
 

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As Jaime says, that is definately a characterisitc of faulty accumulator/s. Supposedly they should be changed every 10 years or so, but I'd wait until I experience symptoms like yours. The accumulators are effectively the SLS system springs, and when faulty have no spring-like characteristics at all.

Alex


jamgusa said:
If it's bouncy I would definitivelyt check the accumulators, and while you're at it check all hoses (there are five: one going to each of the schocks and three to and from the regulating valve) especially the high pressure intake one.
Mine were responsible for that.
Jaime
 

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Thanks guys. Sounds like a few things to check and exactly the sort of advice I was after! From past experience, if I had taken it to my local dealer, I would have been told 'needs new shocks!'. It happened with the fronts, when what I really needed was new top strut mounts!

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Jaime,

Did you replaced all (5) accumulators yourself, how hard was it? Do you need special tools/process when removing them?

My car has over 100K, I may consider doing this soon. BMA quote is about $160 but I am not sure if it is for the pair or ea. Is Febi an OEM product?

Thanks for any info.
 

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Yes and no: a friend of mine did it and I helped him.
The accumulators are two, one for each side,and I got them at BMA (Patrick).
The hoses are 5: one from each shock to the accumulators and three that go into the regulating valve. (BMA too).
It's a difficult job only because you need a lift and need to get the exhaust completely off. Some of the hoses were rusted and it was not easy to get them off (WD40: what a wonderful invention!!). Plus you have all the Pentosin leaking out which makes a mess of whoever is working, and you have to refill and bleed the system, which is the easiest part.
In all it took 3 hours for the accumulators and the two hoses and another three for the remaining three hoses as we did it in two shifts at different times. When you change the three valve hoses you really need to get the valve and the bracket with the rod out of the car: access is really difficult.
I also got one of the rear shock mounts changed while I was at it; but in the Touring you have to get access to it and you have to dismount all the side panels inside to get to the top of the mount, which took me a while as I prepared the car for the job.
One thing is important: after 130,000 miles they really needed changing, absolutely a must, even before, I think.
I'm not sure about FEBI but Lemforder is definitively OEM; Patrick at BMA will tell you and he also has a list of the parts he gave me.
You can check the parts out at:http://www.realoem.com/, just type your vin number in.
Jaime
 

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Oopss, this maybe a little complex for me. Need to do plan B.

Do you need to reset the ECU after completing the change over?

thanks again.
 

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It's not really complex just time consuming and you do have to have a good set of comprehensive tools as some nuts and bolts are really difficult to get to.
I did not even look at the ECU. I don't think it knows that anything went on, and it's never given me any signal whatsoever.
One thing you might do at the same time is checking the drive shaft.
Mine was in really bad condition: the center bearing was completely shod (and I knew about this as I had a LOT of vibration in 1st and 2nd gear at around 30/35 mph) and the rear CV joint needed refurbishing.
I took the whole shaft out. took it to a Driveshaft rebuilder (DRIVELINES Inc
in IRVINE CA 949-951-9673) where in 4 (four) hours they custom refurbished it completely (new bearing, new CV joint) , balanced it and painted it all for
$ 317 including tax! I was truly amazed.
Jaime
 
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