[Smchuck]

what is this part sticking up through the rear upper control arm. The other end is connected to what looks like a position sensor. the end sticking out isn't connected to anything. thanks

 

[Inlajnsiksbenzin]

It´s for headlights leveling. It adjusts your headlights when weight is applied to the car so that you will not blind other drivers i think.

 

[MJC12]

It´s for headlights leveling. It adjusts your headlights when weight is applied to the car so that you will not blind other drivers i think.

If this is the rear control arm then probably not, the leveler is on the front control arm.

Looking on realoem I don't see anything quite like that thing for my model. Recommend looking up the rear control arm assembly for your model to see if anything comes up.

RealOEM.com - Online BMW Parts Catalog

BMW parts 3' E46 330i Rear axle support/wheel suspension

www.realoem.com

EDIT: Looks like I might be wrong about the headlight leveling only being on the front suspension. The part may be the "Regulating Rod" from this diagram.

RealOEM.com - Online BMW Parts Catalog

BMW parts 3' E46 330i Headlight vertical aim control sensor

www.realoem.com

 

[Inlajnsiksbenzin]

I thought it was on the front but on the back also...i have it too and my car is equipped with xenon headlights. When you put weight on the back of the car the light from headlights will shine under different angle, thus it also needs some data from the rear box. What else should it then be?

 

[MJC12]

I edited my post, turns out there are leveling components in the rear as well that I didn't know about.

 

[MrMCar]

On newer generations of cars (take any higher power F series BMW) the sensors can also be incorporated into the DSC system. Yet another tidbit of information about the position of the suspension added into the mix when the ABS/DSC system needs to make decisions about corrective action needed to right any car "out of shape."

 

[Alex323Ci]

it’s the xenon headlight leveler sensor. there’s one on front and one on back.
yours appears to have a broken balljoint arm.

 

[Smchuck]

It´s for headlights leveling. It adjusts your headlights when weight is applied to the car so that you will not blind other drivers i think.

Thanks