Sudden 'extra' or 'opposite' steering!

[CFSD]

Hi forum,

I have a problem with my 2012 e89 MSport 2.0 Auto that is pretty hair raising and at the same time apparently not diagnosable by my garage.
Here is the issue.

Occasionally (by that I mean at least once every trip these days)!!! The car will either suddenly add some additional steering or suddenly reduce the steering without any movement of the steering wheel. This can occur when going around a roundabout (sudden steer reduction - i.e. the car seems to want to straighten up) or when changing lanes on the motorway (car acts like a drunk wasp), or when on a steady bend (extra steer or reduced steer depending on direction).
It's more noticeable in Sport mode, but still there in Comfort. Can't be made to happen deliberately though, by going round and round a roundabout for example. It doesn't happen all the time either, I can't figure out a repeatable way to 'prove' to my garage it's happening...
It's a very sudden movement. There's no notching when turning the steering wheel.
The garage keep insisting there's nothing wrong, but there most certainly is and it's leading to me not trusting the car.

Any ideas out there?
No traction control light when 'wandering' on the motorway, but I have seen it flicker occasionally when it happens on a roundabout or gentle curve. Not driving aggressively or even in a lively way... in fact I'm now driving it like it's made of glass!

Cheers.

 

[Deepseaskateboard]

The only way you can rule out driver error is to have someone else drive the car for an extended test drive over a few days.
Have the garage drive the car to and from work for a week etc.

If someone else can replicate the issue, then you may be able to have them investigate further.

The other way is driving another e89, and see if that does it too.

 

[Deepseaskateboard]

The only other thing which comes to mind is the condition of your tyres.

How old are they, what brand, how much tread etc?

This may be the obvious jumping off point. The tyres can be worn on the inner edge, so best to get the car in the air for an inspection.

If you have 19” 326m wheels, do they have any cracks?

 

[CFSD]

I understand what you are saying, but I can be 99.9% certain it's not driver error.
The fronts are less than a year old, rears less than two with lots of tread. Bridgestone Potenza all around.
No cracks in the alloys and pressures are all correct and stable.

All the 'obvious' stuff has apparently been check by the garage which is why I'm trying the hive-mind of the forum. Just in case there could be a spark of a clue here.

Cheers.

Also. I've had the car a few years now. This is a new development.

 

[Pondrew]

Any ideas out there?
No traction control light when 'wandering' on the motorway, but I have seen it flicker occasionally when it happens on a roundabout or gentle curve. Not driving aggressively or even in a lively way... in fact I'm now driving it like it's made of glass!

Cheers.

Is it definitely front steering and not the car rear steering, ie DSC playing up? The DSC will apply braking to each rear wheel independently if it thinks it is required. Try switching the DSC off and see if that stops it.

 

[CFSD]

Is it definitely front steering and not the car rear steering, ie DSC playing up? The DSC will apply braking to each rear wheel independently if it thinks it is required. Try switching the DSC off and see if that stops it.

Good question, It's hard to tell really. I'll try that and see if it makes a difference.

 

[Pondrew]

If it is one of the rear brakes 'grabbing' it could be as simple as sticky rear calipers.

 

[Argyll Andy]

Re the observation of it, do you have, or access too, a GoPro or similar?

Set up to cover steering wheel and forward view of the car and see if it can pick up the point it happens for you to evidence. The “ohhhh Sh!t” comment in the commentary will let the garage know the exact point of occurrence

 

[B21]

The first port of call is a decent code reader…does the garage have one, know how to use one etc…

I would plug a decent diagnostics tool and see what the various systems..DSC and steering ECU are saying..

What year / model is the E89?

 

[brillomaster]

i had something similar on an E85 a while back... car felt really weird through some corners, very unstable. Turned out a fairly major bush in the rear suspension had completely collapsed, so the suspension was moving around and was getting a lot of dynamic rear toe changes.

my other thoughts are tramlining - you running runflats?

or, something regarding power steering assistance - if assistance is lost, car will want to straighten up suddenly?

 

[buzyg]

I was having similar ideas as Brillomaster. Tyres or the power steering cutting out intermittently, I had that on a Nissan Primera, put the willies up me, until it was sorted. Would expect the second of those to through up an error code.

 

[flybobbie]

Today going to work steering on my car felt strange.
I always felt it took more effort left than right, like the null in centre was offset to right, yet car tracks straight.
Felt like turning steering right it became vague, car felt like it slipped left.
I became wary of hard acceleration in case it veered off road.
I left it at work and came home in another vehicle.
Tomorrow will run the code reader, can see real time steering angle and can reset steering possibly.
I do wonder if a shock has failed.

 

[flybobbie]

Turns out it wasn't the car.

 

[Pondrew]

Turns out it wasn't the car.

What was it then?

 

[flybobbie]

Well been to A and E (although name has been changed now?), seems like a trapped nerve in me.
Checked for a stroke but all ok.

Think i'm getting a bit to old for clambering into the Zed.
Perhaps i should open and close roof to get in

 

[smorris_12]

Well been to A and E (although name has been changed now?),

A lot of trusts now call it ED (Emergency Department)