Jerky/Notchy steering

[meatycabbage]

Hello!

Sometimes when driving my 2003 3.0 Z4 it feels like the steering wheel wants to jerk in a random direction. Doesn’t seem to be any consistency with it, I’ve noticed it at both low and high speeds even on smooth roads.

Michelins on the front and back so don’t think it’s the tires/ tram lining.

Logically I thought it could be an issue with the control arms or eps like maybe the motor is failing but id rather not replace something and have the issue persist.

Most of my research points to “sticky steering” I know the columns can get a bit dry and there’s even a ring that can be adjusted but the fixes seem a bit above my skill set.

There’s not really any specialists around Oxford that I’m aware of so I’m debating taking it to RBM in Hampshire as the previous owner spoke quite highly of them plus it’s only an hour away from me. But if anyone has any suggestions I would definitely appreciate it

 

[enuff_zed]

Sounds almost certain to be the sticky steering which can be adjusted using the spacer ring.
It's not actually too difficult an adjustment to do, but if you've never been into that area before it can seem a bit daunting.
RBM are probably your best bet.

 

[colb]

Sounds like the ring needs adjusting as per the old threads on here to get rid of that sticky steering issue. If you are not confident enough to have a go yourself, RBM would be a good choice.

 

[enuff_zed]

[ref]colb[/ref], we said the same thing in slightly different words.

 

[meatycabbage]

Thank you both!

Looking at videos the ring adjustment didn’t look like the worst job but would rather someone who knows what they’re doing has a look :lol:

Better get on the phone then.

 

[Rucky]

before you start playing suggest you gey it plugged into INPA and carry out the Steering Angle Sensor calibration programme and check live data output lock to lock. There are also issues with the Wiper contacts within the SAS that can get dirty, usually shows up as an intermittent voltage drop o across the wipers. Mine ended up becoming a hard fault and needed the SAS replacing.
I did a post abiut the difference between SAS and ABS faults that show the 3 light " Trifecta" that is often quoted.
You may see the faut 5E40 logged. Steering offset fault. My car started by pulling left like a puncture then clearing, gradually got worse.
Good luck.

 

[meatycabbage]

before you start playing suggest you gey it plugged into INPA and carry out the Steering Angle Sensor calibration programme and check live data output lock to lock. There are also issues with the Wiper contacts within the SAS that can get dirty, usually shows up as an intermittent voltage drop o across the wipers. Mine ended up becoming a hard fault and needed the SAS replacing.
I did a post abiut the difference between SAS and ABS faults that show the 3 light " Trifecta" that is often quoted.
You may see the faut 5E40 logged. Steering offset fault. My car started by pulling left like a puncture then clearing, gradually got worse.
Good luck.

Interesting, I don’t have INPA so can’t really test that but
it definitely has gradually gotten worse over time.

So would a faulty sensor cause the wheel to try adjust thus causing the twitching? I haven’t had any lights show up on the dash.

 

[enuff_zed]

before you start playing suggest you gey it plugged into INPA and carry out the Steering Angle Sensor calibration programme and check live data output lock to lock. There are also issues with the Wiper contacts within the SAS that can get dirty, usually shows up as an intermittent voltage drop o across the wipers. Mine ended up becoming a hard fault and needed the SAS replacing.
I did a post abiut the difference between SAS and ABS faults that show the 3 light " Trifecta" that is often quoted.
You may see the faut 5E40 logged. Steering offset fault. My car started by pulling left like a puncture then clearing, gradually got worse.
Good luck.

Interesting, I don’t have INPA so can’t really test that but
it definitely has gradually gotten worse over time.

So would a faulty sensor cause the wheel to try adjust thus causing the twitching? I haven’t had any lights show up on the dash.

The slight twitch you describe is more symptomatic of the ring adjustment. As [ref]Rucky[/ref] describes, the SAS tends to manifest itself more in a gradual pull to one side.
However, if you don't have the kit to check it you may as well go to RBM anyway and they will check the lot.

 

[Rucky]

I can only give you the benefit of my actual experience from faults and repairs that I have had to identify and rectify myself.
However, Before it fails and you end up in a high speed swerve into a hedge or worse still another car I suggest you have any recorded faults read which will point you in the right direction for a solution.
If you intend to keep the car it is worth investing in a code reader as you will no doubt experience other fauts and lights that need identifyinhg.
INPA which runs off a laptop is a maintenence and servicing toolset which allows ABS brake bleeding functions, steering calibration etc etc. I also use it on my X5 for ride height setting and calibration and service resets. It has now been replaced by ISTA for newer vehicles.
I am surprised you have not had an warning lights - yet, Good luck

Here is the post I wrote a while back which shows the level of interrogation INPA allows. It was the intermittent SAS Wiper voltage that caused the pull to the left trying to correct a fault that wasnt there - but it soon detected a fault and the warning lights came on!
https://z4-forum.com/forum/viewtopic.php?t=121145.