E85/E86 Steering Problems (Solved)
- Thread starter Joycey
- Start date
Good luck with yours!wonkydonkey
Senior member
There seem to be a few people at the moment suffering from twitchy steering even after they've had a play with the EPS ring, so I thought I'd share my experience below, which might give you some ideas. For background info, I've dialled out the sticky steering on quite a few forum members' cars as well as my own. I had also replaced my lollipop bushes and had the alignment checked, but the car was still nervous and twitchy (the steering wheel was never ever still - always wriggling). Both pairs of tyres were non-run-flats, but the car just didn't like them on the front.
wonkydonkey said:
Southwestz4
Member
I had my steering column reconned at bba reman after awful sticky steering ...all was well but then the car felt loose at around 60mph ...could feel the eps motor doing micro adjustments ...bloody annoying and car did not feel safe at 60mph plus . So I am now mid way through converting it to a hydraulic system. I did not that when I took the old steering rack off it felt very notchy when moved by hand ...car has just ticked over 80k .
All front jounts/bushes have been changed and lollypop are now polybushed...also polybushed trailing arm bushes.
Re alignment done on a hunter machine.
Hopefully the conversion with cure this
All front jounts/bushes have been changed and lollypop are now polybushed...also polybushed trailing arm bushes.
Re alignment done on a hunter machine.
Hopefully the conversion with cure this
enuff_zed
Lifer
An interesting project then, but it sounds like a new rack may have cured it?Southwestz4 said:I had my steering column reconned at bba reman after awful sticky steering ...all was well but then the car felt loose at around 60mph ...could feel the eps motor doing micro adjustments ...bloody annoying and car did not feel safe at 60mph plus . So I am now mid way through converting it to a hydraulic system. I did not that when I took the old steering rack off it felt very notchy when moved by hand ...car has just ticked over 80k .
All front jounts/bushes have been changed and lollypop are now polybushed...also polybushed trailing arm bushes.
Re alignment done on a hunter machine.
Hopefully the conversion with cure this
Should get a few quid back for the EPS motor.
Southwestz4
Member
yes so far it's been easier than I thought. I just need to code out the motor and sort the intermediate shaft out, fit new rack and cooler pipework.enuff_zed said:An interesting project then, but it sounds like a new rack may have cured it?Southwestz4 said:I had my steering column reconned at bba reman after awful sticky steering ...all was well but then the car felt loose at around 60mph ...could feel the eps motor doing micro adjustments ...bloody annoying and car did not feel safe at 60mph plus . So I am now mid way through converting it to a hydraulic system. I did not that when I took the old steering rack off it felt very notchy when moved by hand ...car has just ticked over 80k .
All front jounts/bushes have been changed and lollypop are now polybushed...also polybushed trailing arm bushes.
Re alignment done on a hunter machine.
Hopefully the conversion with cure this
Should get a few quid back for the EPS motor.
I maybe incorrectly assumed the old rack was ok with only 80k on it ...but hey ho ...half way through now so may as well continue
I did a quick check with ncs expert and couldn't find the module that has the settings for the eps motor ?
Can anyone shed any light on it ?
Southwestz4
Member
Having looked into it a bit more I think I will just remove the worm drive on the motor and refit it ...never done any ' proper ' coding and don't want to mess things up !enuff_zed said:
Southwestz4
Member
sorry ...I meant I could not find the module in Ncs expert :headbang:Southwestz4 said:yes so far it's been easier than I thought. I just need to code out the motor and sort the intermediate shaft out, fit new rack and cooler pipework.enuff_zed said:An interesting project then, but it sounds like a new rack may have cured it?Southwestz4 said:I had my steering column reconned at bba reman after awful sticky steering ...all was well but then the car felt loose at around 60mph ...could feel the eps motor doing micro adjustments ...bloody annoying and car did not feel safe at 60mph plus . So I am now mid way through converting it to a hydraulic system. I did not that when I took the old steering rack off it felt very notchy when moved by hand ...car has just ticked over 80k .
All front jounts/bushes have been changed and lollypop are now polybushed...also polybushed trailing arm bushes.
Re alignment done on a hunter machine.
Hopefully the conversion with cure this
Should get a few quid back for the EPS motor.
I maybe incorrectly assumed the old rack was ok with only 80k on it ...but hey ho ...half way through now so may as well continue
I did a quick check with ncs expert and couldn't find the module that has the settings for the eps motor ?
Can anyone shed any light on it ?
ryushe
Member
1 month in, and I still haven't found one for an LHD car. BMW no longer makes / supplies them, and there don't seem to be any aftermarket versions available. Some manufacturers have what seem to be reconditioned racks, but can't get them as a private person. Had a small garage here try to order one from 2 or 3 of these providers, but they say they're not available at the moment / not in stock. Put an alert in for a second hand rack on a partsfinder website that has pretty much all junkyards connected, but outside of ONE reply, nothing serious (the reply was for a rack from a car with 220k+ KM, and which had also been in a full frontal collision, so no thanks).enuff_zed said:
I even tried BMW Group Classic for shits and giggles, the source for all your rare or one-off BMW parts for classics and 'classics', and they quoted an absolutely INSANE amount for a rack.
So yeah, good luck with that.
That being said, very interested in how you get on @Southwestz4!Southwestz4 said:
Southwestz4
Member
That not good ...I didn't realise that the LHD ones were so hard to get hold of !ryushe said:
Maybe the best route is to get yours reconditioned, even if it means sending it abroad to be done ? :?
ryushe
Member
Looked into that as well, 3 different companies here in NL tell me that reconditioning in the case of the Z4 steering rack is no more than replacing seals and regreasing the thing. They can't do shit about any (even slight) wear in the teeth of the gears, which is what I seem to be suffering with.Southwestz4 said:
Next stop is eBay, and hoping that what I find there is in decent shape. Although a cursory glance finds results for racks from cars that are all 100k+ miles
ThePocketGT
Member
Thanks Lee, adjustment made and a vast improvement in the handling. My steering always felt really loose and I found the ring to be in the slackest of positions. I knocked the ring round by 20mm and the steering feels soo much heavier. Test drive for a week and see if it needs more tightening or realising.
Thus is certainly worth doing.....
Thus is certainly worth doing.....
My current understanding is that steering issues (sticky/loose/twitchy/micro-adjusting) come down to two factors: the EPS ring adjustment and the steering rack preload. Additionally, issues with steering rack wear will affect the steering. Both the rack preload and EPS ring need to be properly adjusted and in correct relation to each other to optimize the steering.
Here's what I've learned so far, mostly from forum member @Maklo
- lift the front wheels up in the air, engine off (=no EPS active)
- adjust the steering rack preload as shown in https://youtu.be/9KUJOvYR23A. You don't need to take the rack out of the car to do this. Turn the steering wheel from full left to full right position and make sure the steering wheel movement is equally smooth in all positions. Adjust the preload as necessary until movement is smooth.
- you also might want to clean and lube the rack if it's dry, easiest to do while the rack is out
- adjust the EPS ring just slightly below the sticking limit, probably needs trial and error. The fact that ambient temperature has a role on how the steering behaves, does not exactly help.
Related thread: https://z4-forum.com/forum/viewtopic.php?t=141290&start=30
Here's what I've learned so far, mostly from forum member @Maklo
- lift the front wheels up in the air, engine off (=no EPS active)
- adjust the steering rack preload as shown in https://youtu.be/9KUJOvYR23A. You don't need to take the rack out of the car to do this. Turn the steering wheel from full left to full right position and make sure the steering wheel movement is equally smooth in all positions. Adjust the preload as necessary until movement is smooth.
- you also might want to clean and lube the rack if it's dry, easiest to do while the rack is out
- adjust the EPS ring just slightly below the sticking limit, probably needs trial and error. The fact that ambient temperature has a role on how the steering behaves, does not exactly help.
Related thread: https://z4-forum.com/forum/viewtopic.php?t=141290&start=30
To certain extent it is possible. You need to remove the steering rack boot to uncover the rack. Tie rods might need to come off as well. When you have exposed the rack, turn the steering wheel to extreme position on the driver's side. This will result in most of the rack being visible. Then just clean it and apply moly grease on the rack.2.5tdi said:
The EPS module looks like it's flashable, but so far I've had no success with EPS and WinKFP. There is a newer ZUSB for EPS shown in WinKFP, but at least for me all I get is "no response from control unit" error in WinKFP. I'm planning to try out ISTA/P instead, but I don't have an ICOM interface which is needed to program modules with ISTA/P. I'll probably look into that later.2.5tdi said:
One thing to note about steering rack preload adjustment, and also a word of warning, if you have the twitching or microadjusting steering issue, it does not automatically mean that you need to tighten the steering rack preload. Even though it may sound counter intuitive, it also can be the other way around, you might need to loosen up the rack preload. The theory is that too heavy preload on the rack will mess up EPS which starts doing adjustments. You will feel if there's heaviness or notchiness in the rack when you turn the steering wheel left and right through center while wheels are in the air.
So I went to do this as my steering feels a bit odd at motorway speeds. Sort of constantly sticking/unsticking, only ever so slightly but just constantly adjusting like it’s catching a magnet on/off.
I managed to undo the torx bolts no issue, however the ring seemed to be seized in place? The hole that people were using to put a screw driver was completely inaccessible as it was up in the 2 o'clock position, does this mean it’s already been fully adjusted?
If so, would I need a new rack to fix the issue?
I managed to undo the torx bolts no issue, however the ring seemed to be seized in place? The hole that people were using to put a screw driver was completely inaccessible as it was up in the 2 o'clock position, does this mean it’s already been fully adjusted?
If so, would I need a new rack to fix the issue?