Steering wheel does not return to Center

Its sounds as if you are in need of a wheel alignment. By the sound of it, it appears that you don't have enough caster in your front wheels. The amount of caster can greatly affect how hard and fast the wheel will return to center. It should be around 6-1/2 degrees positive which means that if you are looking at the strut from the side of the car, the top of it should be leaning backward away from the wheel center. That said, something caused this to happen and I'm not an expert on BMW's but I am reasonably sure that there is not an adjustment for caster, only toe. There are aftermarket kits available to adjust caster. But those involve relocating the strut mounts usually. Did someone put one of these kits on perhaps and goof up the installation?

Okay, let me know what the specs are on the wheel alignment results if it still persists. They should give you a piece of paper with the numbers (Camber, Caster, and Toe) I looked up the specs on your car and Caster should be 6 degrees 45 minutes (or 6-3/4 degrees) plus or minus 1/2 degree. So I was close!

Wrong caster settings will cause poor centering. So would worn/binding steering components like ball joints, tie rod ends and a bad steering rack.
Does it return to center at all or do you constantly need to return it to center?

Hello,

If the alignment does not fix it it sounds like the rack and pinion is going out. Here is information (below) on how to replace it, cost and labor time.

Parts Information OEM Part Price
Steering Gear
4 - Steering Gear 32106780124 $2646.65

Complete Assembly With Transfer Of Parts B 6.2 hrs
Does Not Include: Wheel Alignment.

Check out the diagrams (below). Please let us know what you find. We are interested to see what it is.

Cheers, Ken

Something is binding. To be sure of what is going on you can disconnect the tie rod ends with the front ends raised up then steer the wheel and turn the wheels by hand to see what is binding, most liking the rack.

https://www.2carpros.com/articles/tie-rod-end-replacement

and

https://www.2carpros.com/articles/jack-up-and-lift-your-car-safely

Please run down these guides and report back.

Cheers, Ken

So the front alignment was okay then? Just curious, what does it say about Caster? That part was cut off on the picture you attached.

If the caster turns out to be okay, then I would be inclined to agree with Ken in that you have something binding in the front end that is preventing the wheel returning to center by itself.

Jon

For poor return to center the caster would need to be way off. The wrong camber in the rear that picture shows would not cause it. However that reading suggests either worn bushings in the rear suspension or something was slightly bent.
Your issue is in the front suspension, as it was there before the new struts and mounts were installed I would look at other components first. Namely the steering rack, the tie rod ends and the lower ball joints/swivel bearings. It would only take binding in one of them to cause this issue. A simple test would be to jack the front end up enough to get both front tires off the ground. With the engine running, put your hands on either front tire at the 9 and 3 positions and try to turn the tire like you are making a turn. Does it move freely or do you feel an easy then hard spot like binding? If you turn the steering wheel does it feel smooth as you turn or does it get stiffer as you turn it back/forth? Do you hear anything like creaking or popping as you turn the wheel?

Does the sound occur when turning the steering wheel or hitting bumps? Popping is commonly a sound heard when a binding part moves.

Then you have something binding, either in the rack, tie rod ends or ball joints. Jack it up so the front is off the ground and have someone turn the wheel while you listen for the sound. Look at the parts as well. Or find a shop with a chassis ear and they can listen to various parts while the vehicle is in motion. I would get it repaired ASAP as binding like that usually precedes a part ready to fail very soon.