[x5mad]

I have a 2017 340i auto rwd which I bought 2 months ago.

Have found the EPS to be a bit strange in that some days it's as light as a feather and then other days or even same day it feels heavier. I have adaptive suspension and VSS and the heavy steering is only on when in sport + (how I've set it)

Overall the VSS is actually really good, I would not have known my car had it were it not for the specs list. I drove a 2013 loaner with VSS and wow that was awful, it felt so artificial and could not get used to it.

Has anyone with same specs encountered the steering changing like that despite everything else the same i.e. Same road, same driving mode etc

[RoundelM3]

Normal operation with your options.

[HighlandPete]

Originally Posted by roundel335

Normal operation with your options.

How's a different steering weighting on random days a normal operation?

I can understand the variables of the modes and servotronic, for different speeds, etc., but how is it set to be a 'random weight, which the OP is reporting?

If my EPS was different on some days, compared to other days, it would be back to the garage for a solution.

[RoundelM3]

It's a brand-new car with a newer VSS, so it could be a different type of adaptation. The first thing I'd be doing is taking it back to the dealership and have them ride along or drive the car to determine if it is just the way this VSS adapts or if there is a mechanical or electrical fault. VSS supposedly adapts to driving style, not the road or conditions or what mode it's in. Does it work ok in just Sport mode? How about in Comfort mode? Why ask the Forum when it's clearly something that the dealership should be looking into if there's a question about its operation?

[otay]

Originally Posted by roundel335

It's a brand-new car with a newer VSS, so it could be a different type of adaptation. The first thing I'd be doing is taking it back to the dealership and have them ride along or drive the car to determine if it is just the way this VSS adapts or if there is a mechanical or electrical fault. VSS supposedly adapts to driving style, not the road or conditions or what mode it's in. Does it work ok in just Sport mode? How about in Comfort mode? Why ask the Forum when it's clearly something that the dealership should be looking into if there's a question about its operation?

Thought VSS was simply a variable cut steering rack? So, less steering wheel movement required near the center.
http://www.bimmerpost.com/goodiesfor..._Dynamics1.pdf
I suppose EPS boost could be intermittently changing if there was a bad sensor or something, but more likely it's just that you need to get used to it...

Don't have VSS now, but will have it in a couple months, ordered 340i with Track Handling pack.

[chiefneil]

Originally Posted by otay

Thought VSS was simply a variable cut steering rack? So, less steering wheel movement required near the center.
http://www.bimmerpost.com/goodiesfor..._Dynamics1.pdf
I suppose EPS boost could be intermittently changing if there was a bad sensor or something, but more likely it's just that you need to get used to it...

Don't have VSS now, but will have it in a couple months, ordered 340i with Track Handling pack.

Correct. VSS is 100% mechanical, it's simply a variable cut steering rack as you mentioned. There's no adaptation involved.

People are confusing VSS with EPS, which I always assumed has some mild speed-related adaptive qualities but I've never really noticed, personally. Anyway, the point being that any adaptation noticed is due to the base EPS steering system and not VSS.

[HighlandPete]

Originally Posted by chiefneil

Correct. VSS is 100% mechanical, it's simply a variable cut steering rack as you mentioned. There's no adaptation involved.

People are confusing VSS with EPS, which I always assumed has some mild speed-related adaptive qualities but I've never really noticed, personally. Anyway, the point being that any adaptation noticed is due to the base EPS steering system and not VSS.

VSS, like the standard rack, has the servotronic (speed sensitive) function. The programming will be slightly different than the standard rack, to accommodate the faster rack towards lock.

We've been using servotronic in HPAS for years, you should not get any odd under/over assisted situations with HPAS or EPS.

[x5mad]

Originally Posted by roundel335

It's a brand-new car with a newer VSS, so it could be a different type of adaptation. The first thing I'd be doing is taking it back to the dealership and have them ride along or drive the car to determine if it is just the way this VSS adapts or if there is a mechanical or electrical fault. VSS supposedly adapts to driving style, not the road or conditions or what mode it's in. Does it work ok in just Sport mode? How about in Comfort mode? Why ask the Forum when it's clearly something that the dealership should be looking into if there's a question about its operation?

Bit puzzled by your posts. First saying it's normal and now saying not normal and get it checked out?

Anyway, as we all know the technicians all follow a set book of rules and tick boxes i.e. If no code thrown most likely they will just say did test drive, no codes, nothing wrong.

I have a BT cable but for some reason the software just won't load despite previously working. If a code was thrown it would be booked in.

It doesn't happen all the time. Comfort or sport makes no difference. I've set both to have comfort steering anyway.

Example of problem, maneuvering at low speed e.g. Parking , steering is very light. On a different day same conditions the steering is noticeably heavier.

I only mentioned what options I have to give better idea but it would be the EPS causing the problem?

[Wires]

Parking it always feels the same for me. I do notice a difference on the highway depending on the day. The purpose of the EPS is for fuel savings. On the highway, I notice that if there is a cross wind, or you do any twitchy movements of the wheel, then it will start to feel heavy. Otherwise it goes more soft and numb.

[MisterPhilip]

Originally Posted by x5mad

Example of problem, maneuvering at low speed e.g. Parking , steering is very light. On a different day same conditions the steering is noticeably heavier.

I brought mine in for the same thing because I was originally told by sales that it would always be heavier. However, after some discussion with the lead tech, they said that the weight change engages after a certain speed (I don't recall the exact speed, either 25 or 30mph). On the twisties you'll feel it, but in the parking lot you won't need to put more effort into turning. I wish it wish it was an option to always be on, but here we are.

[HighlandPete]

Originally Posted by MisterPhilip

I brought mine in for the same thing because I was originally told by sales that it would always be heavier. However, after some discussion with the lead tech, they said that the weight change engages after a certain speed (I don't recall the exact speed, either 25 or 30mph). On the twisties you'll feel it, but in the parking lot you won't need to put more effort into turning. I wish it wish it was an option to always be on, but here we are.

Don't follow the garage's thinking, or see any logic to a 'switched' speed to the servotronic function.

Never experienced any 'switched' feeling my self, in any BMW steering system with servotronic. ZF data for servotronic (in EPS systems) shows the function (like HPAS) as a map, (steering torque/assistance torque), across the whole speed range. Plus a different map for comfort and sport modes.

I'm pleased my car doesn't display such a 'switched' trait, as described, would find it strange steering to use.

The whole idea of servotronic is maximum assistance at low/parking speeds, reducing assistance as speed increases.

[sakib92]

Hi, was this issue ever resolved as I’m experiencing the exact same problem?