Load-dependent driving behavior of a 1999 Audi A4 with AFB engine

Hello everyone,

My 1999 A4 (B5) 2.5 TDI (AFB) with Eibach sport suspension is exhibiting a behavior that I find strange:
If I (approximately 110kg) am sitting alone in the car, or if my girlfriend (significantly lighter) is also sitting on the passenger seat, the car pulls to the left.
However, this doesn't seem to happen uniformly, but rather appears to depend on how far the front left wheel is compressed (the further it's compressed, the more I have to turn the steering wheel to the right).
Subjectively, while driving, I also feel that the car seems to be more heavily compressed on the left side than on the right.

However, the interesting thing is that my girlfriend thinks the car pulls to the right when I'm sitting in the passenger seat. So, the same problem, but on the other side.

Could a car behave in a way that is so dependent on the load? What could be the cause? The car has 105,000 km on it, of which the suspension has approximately 40,000 km. The problem has existed for about 8 months or 15,000 km. After the suspension modification, the front axle was aligned and adjusted to the Audi Sport suspension settings (as required by Eibach). My 'friendly' mechanic blamed the tires and ruled out the tie rods and rubber bushings as the cause.
Does anyone have any idea what might be causing this? Because I really don't want to have to pay VAG several hundred euros.

Vorab schonmal vielen Dank für Eure Hilfe!

Regards,
Michael Naujoks.

Hi,

Check the strut mounts, or if they're the original ones, it's best to replace them.
It often works wonders.

Best regards, Benno.