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      02-02-2010, 10:23 PM   #1
Mr.Bimmer
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Question Steering Question

I've been noticing the loosness/tightness of the steering wheel when turning is inconsistent occasionally, I don't really like it. Most the time when turning the steering feels loose or atleast normal, which is fine. But when it gets unexpectedly tight during the turn, it's a little startling.

Case in point - the other day I was slowing down from about 60mph coming up on a downhill 15-25mph right hand turn. As I am in the turn, turning the wheel to the right the tightness felt so tight it almost felt as if the power steering literally cut off for a split second - that's how tight it felt. Is this normal?

Car is 100% stock with 1,300 miles. I can't remember what setting I was driving in, I want to say I had 1 EDC light on and S6? but I could be wrong. Outside temperature was about 55 degrees. Has anyone else experienced this or knows what's going on?
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      02-02-2010, 10:41 PM   #2
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Start by checking your power steering fluid. If level is correct, and your power steering pump is not making strange noises when turning your wheels at idle, I'd say it has to be the servotronic valve acting up, since it varies the assist. Only EDC-equipped (tech package) cars have it, like yours.

Start with a fluid check, and report back so one of the experts can help you if needed. But it'd help a lot if you can duplicate it, especially if you need to take it to a dealer; otherwise you'd be most likely wasting your time. Drive your car with servotronic on then off, and slow down on curves like you described above, etc. Good luck.
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      02-03-2010, 12:40 PM   #3
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Quote:
Originally Posted by elp_jc View Post
Start by checking your power steering fluid. If level is correct, and your power steering pump is not making strange noises when turning your wheels at idle, I'd say it has to be the servotronic valve acting up, since it varies the assist. Only EDC-equipped (tech package) cars have it, like yours.

Start with a fluid check, and report back so one of the experts can help you if needed. But it'd help a lot if you can duplicate it, especially if you need to take it to a dealer; otherwise you'd be most likely wasting your time. Drive your car with servotronic on then off, and slow down on curves like you described above, etc. Good luck.
Thanks Elp

I just had my 1,200 mile service done, I would assume the power steering fluid level is okay. I've never heard any pump noises or any strange noises.

What is the servotronic valve?

I can get this to duplicate as the tightness/loosness is inconsistent. Coming home yesterday I was driving straight at approx. 20mph turning the wheel to the left and then right, repeating that motion at a 15-20mph pace. Sometimes the turns felt loose other times they got tighter.
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      02-03-2010, 01:30 PM   #4
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What is the servotronic valve?
It's a valve by the steering rack that changes steering assist on cars equipped with the tech package. No specifics are mentioned on the BMW tech documents I read, but it must have an electric motor activated by the DCM, based on inputs like vehicle speed, etc.

Seems like your power steering system is working fine, so I suspect your troubles (if any -keep reading ) are related to that valve. Dealer can check for codes, but most likely it's software related IMO, due to the intermittent nature of your problem. I've seen all kinds of electronic gremlins reported on this car, and most are erased by downloading the software again (and hopefully with a newer version).

Having said that, your circumstances seem unique, so it could be that the DCM is momentarily 'confused' by how much assist to dial in. I got the impression that valve is working all the time, regardless of mode, so even if you don't have 'servotronic' activated thru the 'M' button, it still provides variable assist in normal mode, which is simply more than on 'servotronic'. I suggest you drive another M3 before letting a dealer mess with your car, since they're not that familiar with M3's idiosyncrasies like owners are. You don't want them messing with a change of pump that requires removing the rack, etc. just to find out it's behaving the same way .

I'd start a thread in the regional forums to see if a nice forum member wants to help you out. Since it doesn't involve abusing the car in any way, somebody should be willing to help you. And even if nobody does, I honestly wouldn't bother with a dealer until it gets worse, so you're sure it's a problem, and not just a trait, like the clunking 6MT tranny, clutch noise with clutch engaged in N, etc. Good luck man.
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      10-20-2011, 12:28 PM   #5
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My experiences are similar, in that sometimes when I start up my car the power steering will be looser than normal and it will be like that for the entire drive. Mines all stock. I haven't had a chance to take it in the dealer yet to inspect.

Any easy way to speak the right language to the dealer so they understand?



Quote:
Originally Posted by Mr.Bimmer View Post
I've been noticing the loosness/tightness of the steering wheel when turning is inconsistent occasionally, I don't really like it. Most the time when turning the steering feels loose or atleast normal, which is fine. But when it gets unexpectedly tight during the turn, it's a little startling.

Case in point - the other day I was slowing down from about 60mph coming up on a downhill 15-25mph right hand turn. As I am in the turn, turning the wheel to the right the tightness felt so tight it almost felt as if the power steering literally cut off for a split second - that's how tight it felt. Is this normal?

Car is 100% stock with 1,300 miles. I can't remember what setting I was driving in, I want to say I had 1 EDC light on and S6? but I could be wrong. Outside temperature was about 55 degrees. Has anyone else experienced this or knows what's going on?
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      12-11-2011, 09:25 PM   #6
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Similar issue here at times I think it's just the way the car behaves.
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      12-11-2011, 10:15 PM   #7
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Guys this has nothing to do with zcp or options since 2011 ateast. Every car has 2 adjustable steering settings. One that is normal and one that is a bit stiffer. Both are fully variable with servotronic with more assistance at low speed and less assistance at high speed.
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