Car pulls to the right under acceleration

[Gabz]

Hi all!

I've been having a bit of an issue for a while now where the car pulls to the right (noticeably) under acceleration. Everything is fine while coasting and braking but as soon as there is load on the back axle, the car pulls to the right to the degree where I can change lanes in seconds just by applying a bit of throttle. Scary and makes motorway journeys constant stress. It's gotten gradually worse and worse over the past months.

Tire pressures and wheel alignment is fine.

I'm thinking that something is loose at the back (bushings, arms etc.) which means that the geometry / toe changes under load. I've been also getting heavy rumbling / shaking at certain RPMs in 1st / 2nd and 3rd gear under heavy acceleration.

Any ideas?

 

[Cees Klumper]

Certainoy sounds like you are onto the cause. Jack it up in the rear and root around with a pry bar, I think you will find something has a lot of play.

 

[R60BBA]

Check your RTABs.

 

[buzyg]

Check your RTABs.

What are RTABs?

Edit:. Rear Trailing Arm Bushes.
https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.youtube.com/watch%3Fv%3DX9HhqLhxKc4&ved=2ahUKEwiqjPCV7tviAhVKRBUIHacxCucQwqsBMAB6BAgKEAU&usg=AOvVaw06-VMgnXABfer0a5PIeUMh

 

[road warrior]

Well I checked and it's..
RTAB-Map (Real-Time Appearance-Based Mapping) is an Open Source RGB-D Graph-Based SLAM approach based on an incremental appearance-based loop closure detector.
So let's go find it people... :rofl:
Dammit Do I need one of these now ?
I'm Still working on the cup holders... :rofl:

 

[enuff_zed]

Had a 3 litre Capri once that did this.
Discovered the rear leaf spring was snapped and only held in place by the axle clamp!!
On the plus side, overtaking was easy; floor the throttle and the car snapped to the right side of the road. Get past the traffic and lift off, and it automatically went back to the left lane.

Yes, yes, I know Z4s don't have cart springs, but it still points to rear suspension issues, mis-aligning the rear track when extra torque is applied,

 

[Nictrix]

While changing the rear springs on our 23i one of the rear droplinks snapped.
Not sure if this would cause what you are describing but wouldnt help.
Easy enough to check them, just take a wheel off and check if the droplink is still in one piece.