Matouti

Hello all,

I have already made a topic for some wobbles on the road few month ago. Especially wobbles/kickbacks over bumps.

It is still here to this date. So i abandonned and decided to ask BMW that took the car for a diagnostic.

The mechanic told me that it was... nothing. For him the car is fine and there is no issue. He took it for a ride on a bumpy road and highway. He noticed the wobbled at around 80km/h and qualified them of small and bearely noticeable (For me they are really annoying but..)
He advised me to do an alignment that could help, but on the receipt they said there was no issue whatsoever, so i have no garantee.

He controlled the rack and suspesion components and are fine, he noticed the new arms and rods. He thought it was accidented because they were changed.

I'm here to ask you, is it normal to have steering kickbacks on this car ? I mean the closest car i drove was my brother's e93 and it doesn't have any. The steering sometimes goes +/- 60° on one direction when on bumps.

I mean I'm surprised. It's either he missed the issue or i'm really picky.

Thanks all for any clue,
Matthieu

habbyguy

Explain that 60° "thing" on bumps. If it's the steering wheel, I'd say sell the car since it's possessed, and is likely to break one or both of your arms!

Matouti

Yes. The car is possessed. I mean it feels like someone else is driving when that happens.

The steering wheel rotates left or right a lot when going over bumps. Much more when going slow but I can feel it on the highway too. It's not as planted as It should.

twh

Just a thought. Have you had a look at the steering column pinch bolt? The steering column comes out of the cabin into the engine bay and has a spline on the end of the shaft. There is a bolt that is commonly called a pinch bolt that connects that spline to another shaft. I've see loose pinch bolts before, including on my parents Land Rover, and it can cause concerning steering movements.

It sounds unsafe to not get this resolved. Something is very wrong and I'd be concerned you lose all steering at the wrong time.

Matouti

Yes I am concerned and I stopped driving the car until I went to bmw. But for bmw nothing is wrong in their opinion even after a road test. That's what I'm more concerned about ahahah. Like they don't want me to pay for any replacement part?? Crazy.

I haven't checked this pinch bolt no. Do I have to remove something underneath or its from the engine bay?
I saw online that air In the steering fluid could also make issue like that?

habbyguy

By "a lot" I'm going to assume that you mean "way, way less than 60° deflection of the wheel"). That is, unless you're doing something odd like going over sharp speed bumps not holding onto the wheel (where significant deflection of the steering wheel WOULD happen naturally). Remember that the steering wheel is there to transfer force from the steering wheel to the front steering knuckles (that hold your wheel bearings and hubs in place). That mechanism works both ways, which is good - since that's what provides the famous "steering feedback" that BMWs are known for. Some other luxury cars try to minimize this, which makes it feel like the steering wheel isn't connected to anything. Yeah, some people like that, but I like being able to tell what the road "feels like".

If the car is trying to wrench the steering wheel out of your hands when you hit a bump, then park it and have it towed somewhere with competent mechanics. But it does sound like the mechanic at the shop you're going to is trying to tell you you're feeling "normal feedback" from the steering system.

Or maybe your previous cars were of the "disconnected" type, and what you're feeling IS normal.

It's a subjective thing, and we may be picturing very different scenarios. Maybe you could describe what's really happening. From your previous description, the wheel is being violently rotated 60° (maybe 9"?) when the front wheels hit a bump. That would - at a minimum - result in a MAJOR change in direction, even at low speeds...

Matouti

Thanks for your answer habby.

It looks like . Next time I'll take a video of it. I know where I live that the paved roads are shitty, but still, with the X3 they gave me (with electric steering ok) it was not moving an inch.

It makes- mechanically speaking- sense that I have feedback and that the steering wheel moves over asperities of the roads. But it is a lot more feedback that I was supposed to have from bmw ahah

habbyguy

SUV drivers typically don't care about "road feel", so the engineers try to engineer it out of the feedback.

Sedan (and wagon) drivers DO tend to want to feel what the road is trying to tell the driver, so the wheel SHOULD move in response to bumps, pot holes and other maladies.

I can't tell if the road in the video is particularly bumpy or not (that would be a LOT of movement for a "smooth road").

I suppose my best response is "I don't really know how much my steering wheel moves over bumps when I'm not holding it" because "I'm always holding it". If I can feel the bump, but the car's not fighting me for control, I'd put it down as a feature, not a problem. ;-)

Matouti

Thanks for your advice. I mean before I have always driven boring company cars and my only vehicle was a motorcycle aha.

Well, I do feel the bump on the steering but I don't necessarily need to fight or add more force on the steering to correct it.

If the road was bumpy on the video as said on the title, would it make sense for you to have this kind of behavior on the steeeing?

habbyguy

I'd say yes. This can be a difficult subject because the forces involved are very subjective. And I'm far from an expert on bumpy roads, living in the Phoenix, AZ east valley (nothing but smooth, flat roads everywhere). I'll try to remember to "test" my car by going no-hands over a speed bump at an angle, and see how much deflection I get.

But otherwise, I have to say that my E61 has the best road feel of any car I've ever owned... well, other than my E46 330i ZHP, and my Fiat X1/9 (I often claimed that not only could I feel if I drove over a penny, but I could tell if it was heads or tails). Of course, no other element of the Fiat's ride "quality" was anything like my (much larger, much heavier) E61 (thankfully). That X1/9 was kind of a cross between a Ferarri and a go-kart. ;-)