Lift Test: Drive Mode & Functionality Check

Hello,

An A5 3.0 TDI quattro is experiencing issues with the drivetrain (the steering wheel shakes/vibrates at certain speeds; brake discs/wheel bearings/wheels have already been replaced).

Now, the car will be run on a lift to see where it vibrates or shakes, but the ABS/ESP system is intermittently interfering with the process.

This feature, which is currently enabled in test mode or a similar configuration, should now be disabled. Does anyone have any ideas or suggestions on how to do this?

Best regards, Rainer.

Quote:

Does anyone have an idea or a tip about that?

No to test stand mode. What comes to mind immediately --> ABS/ESP - disconnect power - remove the fuse.
If no one has a better idea, it's worth a try.

Can the vibrations on the lifting platform be simulated with and without a load?

If a joint in the front drive shafts is affected or jammed, it can become difficult if the drive shafts are hanging downwards (which changes the angle of the joints, and they may not be causing pain).

Hi!

I'm saying that based on my experience, nothing will work out on that lift platform.

Have you tried to see if it only happens under load, or if it also occurs during periods of low activity?

I've also experienced situations where some tire dealers didn't balance the tires correctly, or the balancing machine wasn't accurate.
I once had a similar problem with both my summer and winter tires because the tire shop didn't properly balance either set.
If this issue occurs even without a load, and at speeds around 60 km/h, and perhaps reappears at 90 km/h, then a thorough inspection might be advisable.

Some car models are very sensitive to that.

If things aren't working, maybe try removing the boots from the front constant velocity joints.
Check if there's enough fat in it, and see if it's dried out.
If there is a suspicion, you can also inject some oil to test it.

Can the ESP (Electronic Stability Program) be turned off, or is the A5 an exception?
Otherwise, I wouldn't expect much from the lift test; a better approach would be to fine-balance the vehicle using rollers under the front wheels (without external power!).
Based on experience, the problem is usually caused by the wheel, the brake disc, or the hub. Is the assembly correct (clean, proper torque applied)? Do the tires/wheels have any runout? Some may also develop flat spots, which may only resolve after a few kilometers of driving (or not at all). Where did these parts come from?
The A5 probably doesn't have hubcaps, as they can cause vibrations and uneven wear when not properly centered.
Sure, here's the translation:

"Best regards," or "Sincerely,".
Herbert.