The last weekend at the track (N

 

My first guess would be road imperfections.

Second guess would be tires.

Third guess would be some sort of aero problem. This would require it to be happening at approximately the same speed every time (actually the same Reynold's Number, which depends on speed).

Fourth guess would be some kind of "stiction" problem with the suspension (suspension travel sticks momentarily, then breaks free).

Fifth guess is some kind of problem with the EPS system.

Or maybe it's just your mad driving skilz.

 

I thought at first it was something with the EPS. But there seems to be no "play" in the steering at all.

It's really hard to reproduce. Only sometimes at slow speed (50kmh) right corners can I get it to happen about 25% of the time. The steering wheel is at a 45

 

Mike's guesses are good, but Robin's earned enough "track cred" here that I'd order them in reverse; i.e., I'd suspect something is genuinely wrong (not just surface or tires). Robin, you may have stumbled on to a new "feature" of the S. I'd have both the suspension and EPS thoroughly checked out, and please report back to us on what you find.

 

I had the same problem in my s2k before.

Reset the EPS using the Helm manual docs. It needs to be trained for torque settings.

 

No Helm in Germany. Simple job to reset (like a fuse pulling) or a $tealer procedure?

///Robin

 

Today I noticed that the car wants to steer by itself even when traveling in a straight line! Again, after a few hundred metres, the behaviour stopped.

///Robin

 

Um, I assume you mean something other than normal tramlining? Here in the US, anyway, the grooves worn into the road are bad enough they can tend to pull car into them.

Robin, I would definitely be doing some intensive EPS diagnostic testing if I were you....

 

Just a WAG here, check the upper arm mounts to see if the spot welds have seperated.

 

Rename her Christine and be good to her... She'll take care of you.

Sorry, I've nothing constructive to add...