Any BMW Techs here?

[Speeddog]

My girl's got an '05 Z4 with the dreaded 'sticky steering' issue.

Looking for a DIY solution, or at least a reasonable cost solution.

[pigmy]

gday nick,ive got a bmw m3 95 model that had similar symptoms.i found two things.first under the steering wheel of my car is a plastic
              bearing assembly which i replaced.but the symptoms still continued to a lesser degree.immediately behind the firewall where
              the steering arm protrudes into engine bay ,you might find it very close to exhaust.this part of the assembly drys out and just
              may need a good lube.it worked for me.hope this helps.if not try a search on bimmerfest and bimmerforum.....cheers pigmy

[Speeddog]

pigmy, thanks. 

I'm not 100% sure, but I think
I've checked on bimmerfest and bimmerforum, seems like replacing the whole steering column and rack is the usual solution. 

[ducpainter]

pigmy, thanks. 

I'm not 100% sure, but I think
I've checked on bimmerfest and bimmerforum, seems like replacing the whole steering column and rack is the usual solution. 

For the BMW shop...

or the DIYer?

[Speeddog]

For the BMW shop...

or the DIYer?

For the shop.

Nobody's fessed up to a DIY.
Seems it's only been warranty, out of pocket at a shop, or 'live with it'.
And the warranty & out of pocket at a shop have been at minimum a steering column replacement.
New price is ~$2.5k.
Used is $550 and up, of course, no idea if used unit is any good at all.

This is an electric power steering setup.

[caperix]

The motor for the electric power steering is integrated into the upper steering column.  Not aware of any cheap fixes, but do make sure your charging system is working properly as I have seen low alternator output cause stiff steering at idle.

[Speeddog]

Steering is sticky at all engine speeds.

Stickyness is dependent on interior temperature, when it's cold, it's fine.
When the interior gets warmer, it gets sticky.

[capt steubing]

Just have your chick do some chin-ups, and a few curls, problem solved!

[mitt]

Steering is sticky at all engine speeds.

Stickyness is dependent on interior temperature, when it's cold, it's fine.
When the interior gets warmer, it gets sticky.

Seems like the warmth might be expanding a part that is causing mechanical interference some how? 

mitt

[Speeddog]

Seems like the warmth might be expanding a part that is causing mechanical interference some how? 

mitt

Given the rather small temperature changes involved, IMO it's got to be a plastic bushing that's expanding enough to bind it up.

If the used ones were cheaper, I'd get one and crack it open to try and find the issue.

[caperix]

How much does it stick?  Does it "break free" once the wheel is turned some or is it always stiff?  Is the "EPS", steering light on in the dash?   There are some plastic bushings at the firewall, though those usually just produce a noise when they stick.

[Speeddog]

It is sticky, then breaks free, then sticks again.
Can't really drive straight, it's a constant series of over-corrections to each side.
Very fatiguing and annoying.

Don't recall seeing an EPS light on in the dash.

[mitt]

It is sticky, then breaks free, then sticks again.
Can't really drive straight, it's a constant series of over-corrections to each side.
Very fatiguing and annoying.

Don't recall seeing an EPS light on in the dash.

I have seen plastic to plastic rotary parts have this exact behavior in my design work.  The initial resin rich smooth surface finish wears out, and a slightly rougher surface of fillers / fibers emerges, and is like having sand paper to sand paper friction (not that extreme of course).  I have seen it get so bad, that eventually the parts "plastic weld", or lock together after enough rotary operations, and are basically rendered useless.

The solution I have implemented is using a plastic safe grease on the rotary interface, and bingo, the problem went away.  That was applying grease to new parts, then retesting of course, not trying to retro fix a problem assembly. 

Not sure you can apply this experience, but good luck.  I can see it would be annoying as h3ll having a stick stick stick when you are trying to keep the wheel straight with little corrections.

mitt

[teddy037.2]

where's mac900?

he fixes bimmers for a living  

[Howie]

Speeddog, have you spoken to some dealers about this problem?  It sounds alot like possible NHTSA recall fodder,  "Binding steering may lead to a loss of ability of the driver to change direction of the vehicle and cause a crash, possibly injuring or killing diver and passengers".  There might be a "customer good will" policy on this.