Steering not self centering

[Lotustom]

Booked in on Thursday with a rack reconditioner for them to take a look. He has heard of the problem and has a

I'd also like to hear what he says about it. The worm gear design is not ideal in my opinion. But maybe there could be other problems that make it worse. I am thinking of disassembling the electric motor to determine the stiffness of the steering rack itself. And then drive to see if it centers. I had adjusted the wheel alignment for more toe in but that did not solve the problem.

 

[TedStriker]

I'd also like to hear what he says about it. The worm gear design is not ideal in my opinion. But maybe there could be other problems that make it worse. I am thinking of disassembling the electric motor to determine the stiffness of the steering rack itself. And then drive to see if it centers. I had adjusted the wheel alignment for more toe in but that did not solve the problem.

I dismantled my spare rack yesterday as far as I dared (as it's a working rack). Managed to remove the motor but not the pinion drive. That seemed to make little to no difference to the feel of the input shaft. It looks like it'll take quite a lot of dismantling to remove the pinion drive so I'll wait until I've spoken to the reconditioner before risking breaking the spare rack completely!

 

[crp]

I've read of many people putting spacers on the wheels of their i3 in order to achieve "more stable" road manners for highway driving. I think that there are a lot of factors that play into how the i3 feels as you drive it.

 

[Tecam]

I'm pretty sure the lack of self centering is a result of stiffness in the rack, not an inherent design feature of the i3. But I would like to hear from someone (anyone!) who says their i3 does self centre as you'd expect. I've read/seen plenty of reviews which mention excellent feedback from the road but I get virtually none.

For my entire driving life (35 years/50+ cars) I've never driven anything that doesn't self centre unless it has a fault. On all other cars you can tell if your alignment is out by the car pulling to one side or the other, or tracking straight with hands off the wheel. My i3 pulls to the left, pulls to the right, or goes in a straight line purely depending on where the steering wheel is left.

Come to think of it, I regularly drive on the A14 in UK - it's a road heavily used by large trucks and has quite severe dips where the truck tyres have worn the surface down. In my partner's VW Polo you barely notice when you go in and out of them, in my BMW 435d with wide, staggered wheels it's definitely noticeable but easily dealt with. In the i3 you have no notice then suddenly the car will veer off in one direction and need to be caught. It's like there is absolutely zero feedback from the wheels to the steering wheel so you don't feel the wheels being pulled slightly to one side and naturally correct it.

My 2019 120 steering self centres absolutely fine - as others have said, the car is quite twitchy in crosswinds (particularly on the motorway if you’re going above 60), but apart from that, it’s no different to any other car I’ve owned (I’ve owned a lot & have been a mechanic for 50 odd years).

 

[TedStriker]

My 2019 120 steering self centres absolutely fine - as others have said, the car is quite twitchy in crosswinds (particularly on the motorway if you’re going above 60), but apart from that, it’s no different to any other car I’ve owned (I’ve owned a lot & have been a mechanic for 50 odd years).

That's great to hear, as it means I'm not on a wild goose chase or going mad - but it's also concerning to hear how many i3 owners seem to have the self centering/stiff steering problem. I will get to the bottom of it!

Just to confirm - if you are driving straight and you turn slightly left or right then let go of the wheel, the wheel returns to the centre and the car doesn't keep turning in the direction you turned?

Thanks

 

[Tecam]

That's great to hear, as it means I'm not on a wild goose chase or going mad - but it's also concerning to hear how many i3 owners seem to have the self centering/stiff steering problem. I will get to the bottom of it!

Just to confirm - if you are driving straight and you turn slightly left or right then let go of the wheel, the wheel returns to the centre and the car doesn't keep turning in the direction you turned?

Thanks

Certainly does!

 

[TedStriker]

Steering rack reconditioner has confirmed that the rack shouldn't feel like it does. He believes there's corrosion on the rack rod itself and it's binding on the bushes. Sounds like it's a very common problem, affecting a large percentage of i3's.

 

[Lotustom]

Good to hear where the problem probably lies. Does he think this can also be solved? If this happens regularly, there is little point in buying a used steering rack. I'd love to hear how it turns out.

 

[guido]

Hello Ted, Brilliant investigation. My 2017 REX has the same problem. How did you fix it eventually?

 

[TedStriker]

Hello Ted, Brilliant investigation. My 2017 REX has the same problem. How did you fix it eventually?

This is an ongoing issue. Due to cost of a recon, I'm not sure at the moment if I'm going to go with a recon or just a new/low mileage used part.

As this seem to be a common fault on i3s, often dismissed as 'that's just the way they are', I do wonder if this is partly caused by the steering rack being far forward under a frunk that has no engine to create heat and also permits the entry of water/rain. On the vast majority of (ICE) cars I've owned, the steering rack has been behind the engine, protected from the elements with no chance for any moisture to stay around for long due to heat.

 

[guido]

I will try to have the rack greased, to see if there is a difference.

 

[Sideways]

All modules (inc EPS) updated to 2024 firmware, no change in steering. Replacement rack time I think. According to BMW you have to drop the front axle, which looks like a huge job. The rack is quite visible below the frunk so I'm hoping it's not as drastic as BMW say!

Mine is early 2017 Rex and exactly the same as you describe. TBH I think it's just a poor design. I'm ex-motor trade and have driven thousands of cars having MOT'd about 60+ per week. This is just one item that I put up with. I don't particularly like the car but it costs sub 3p a mile to run so as a spare it's OK. I have solar and a Tesla battery. It's the last car I choose to drive for anything more than 20miles...

 

[TedStriker]

I will try to have the rack greased, to see if there is a difference.

In my case the reconditioners think it's the bushes at each end of the rack, inside the body of the rack housing. I guess it's worth a try to remove the tie rod boots, turn the steering to each end and get some grease in there and see if it makes a difference. I may try that before replacing the rack as it's a lot easier!

The only time I've come across something similar was on the gearchange mechanism on a Mk4 Golf. That had a shaft with a teflon bush inside a slightly larger housing. The aluminium housing had 'corroded' insofar as aluminium can, and the 'corrosion' was squeezing the bush hard onto the shaft and making gear changes stiff.

Further investigation is indicated....

 

[alohart]

As this seem to be a common fault on i3s, often dismissed as 'that's just the way they are', I do wonder if this is partly caused by the steering rack being far forward under a frunk that has no engine to create heat and also permits the entry of water/rain. On the vast majority of (ICE) cars I've owned, the steering rack has been behind the engine, protected from the elements with no chance for any moisture to stay around for long due to heat.

For what it's worth, we bought our 2014 i3 new only 3 months after it had been manufactured, so the rack wasn't likely corroded yet. There was stiction at the steering center point from day one. It got no worse during over 7 years of ownership living next to the ocean with a salty, humid tropical climate where corrosion is rampant. So in the case of our 2014 i3, rack corrosion doesn't seem like the likely explanation.

Our subsequent 2019 and 2021 i3's have no stiction at the steering center point.

None of our i3's has had a strong steering centering force. However, I have adapted to their steering without even being aware which might say more about me than our i3's.