wheel alignment ACC?

[RSVI]

Went to get the geometry done yesterday, same company I've used for years, trusted.

They said they couldn't do it due to after the work, the ACC needs re-calibrating?...

Anyone shed some light on this please, are they right?

(had to have the ACC re-calibrated 2-3 weeks ago!!!.... )

[MikeFish]

I took mine to kwik fit (that was a mistake for a number of reasons!!!never again) and after f'ing about for ages decided they aren't allowed to do it becuase my car has ACC. Apparently they adjusted a BMW with it and it caused all sorts of problems so they just point blank refuse to do any cars with ACC now.
Anyway, took it to my local specialist and they sorted it with no issues. Made a big improvement to the handling. I didn't get the ACC calibrated afterwards and it still works just as intended.

[zebede]

Same issue but worse as mine has cameras all round which - apparently - is worse to do than acc!!

[doodlebug]

I took mine to kwik fit (that was a mistake for a number of reasons!!!never again) and after f'ing about for ages decided they aren't allowed to do it becuase my car has ACC. Apparently they adjusted a BMW with it and it caused all sorts of problems so they just point blank refuse to do any cars with ACC now.
Anyway, took it to my local specialist and they sorted it with no issues. Made a big improvement to the handling. I didn't get the ACC calibrated afterwards and it still works just as intended.

Question. How would you know it wasn't working as intended?

[MikeFish]

I'd have to brake to stop me hitting the car in front or find it brakes too early.

[doodlebug]

Fine margins. The point I was attempting to make is that you'd not know for sure without having it checked.

[MikeFish]

I don't see how an alignment is going to affect it in any noticeable way. Lowering should affect it more and even then it didn't make any noticeable difference.

I know the point you're trying to make but it still works. If I found it wasn't working like it should then I'd have it recalibrated. However, I'm using ACC every day in various conditions including stop start traffic without any issues. Surely a boot full of heavy things would lift the front of the car higher than any difference an alignment would make yet the car still adapts and copes. It's a clever system, adjusting toe isn't going to confuse it.

[RSVI]

Ok, so we agree the ACC (plus optional 360' cameras if fitted) needs to be recalibrate after the alignment's been done.

I mentioned my ACC was recalibrate a few weeks back, this was for a new bumper fitment.
Little bit pi$$ed I wasn't told when Audi did the calibration, would have been nice for them to say, 'it makes sense doing a geo at the same time Sir'...

Ah well, guess I'll have to phone Monday and find out

[MikeFish]

Ok, so we agree the ACC (plus optional 360' cameras if fitted) needs to be recalibrate after the alignment's been done.

I mentioned my ACC was recalibrate a few weeks back, this was for a new bumper fitment.
Little bit pi$$ed I wasn't told when Audi did the calibration, would have been nice for them to say, 'it makes sense doing a geo at the same time Sir'...

Ah well, guess I'll have to phone Monday and find out

No, I don't agree. I've had mine lowered and aligned and I have ACC and 360 cameras and I've not had it calibrated yet. No issues with any of the equipment. I'm not stopping you from doing it, just saying I can't tell any difference.

[RSVI]

I'm not disagreeing with you Mike, but surely the cars safety equipment/computers would know the difference more than us behind the wheel, assuming we're in full control of the car?

I'm happy trusting 'Guildford tyres' opinion, telling me they'd rather not take my money as the ACC should be recalibrate after. After all, they could have taken my money and done the work, but they were honest by repeating what their system was telling them.

If it were 'Quick Fit' telling me, I'd certainly get a second opinion.

I'll speak to Camberley Audi During the week and see what they say.

[RSVI]

'Assuming we're in full control of the car' - meaning...

We think we have full control, unknowingly that the car is being a bit of a guardian angel looking after you all the time.
If adjusting wheel/suspension settings, causes the ACC to be out by a %, even a small %, I'd be happier getting it calibrated back to as it should be.

Doing over ###mph, it's nice to have a wide eyed angel on your shoulder looking over you, not an angel that's maybe suffering a hangover.

[MikeFish]

Audi will ayways tell you to recalibrate as it covers their back. My point was you were asking if it is necessary; Audi will say yes but I've done stuff to the car without recalibrating and it still works. I'm not trying to discourage you, recalibrate if in any doubt is a safe way to do stuff, I'm just giving my experience.

[RSVI]

Cheers

[wildbore]

The limit of change on the rear axle toe-in is 30 minutes before you need an ACC recalibration, IIRC (I have it written down somewhere, I will see if I can find it).

The RS6 is particularly sensitive to geometry changes as it uses twin radars - each of which is partially looking into the adjacent lanes when the car is pointing straight ahead; this is so that it can better track the car in front through a curve (single lensed systems are more prone to losing sight of the car in front in curves). A change of one degree in radar alignment means that the car can unknowingly track a car in the other lane rather than the one you are in.

If you doubt the delicacy of the system, see how well it tracks a car ahead through a curve such as the one on the M40 north of Oxford - even when set at Distance 4 and you can clearly see that the car in front is way off being in front of you (if you see what I mean). ACC should still be locked onto the car in front.

[MikeFish]

I agree with what you are saying especially about a change of degrees of the radar, but I don't understand how changing front toe affects the radars ability to do its job. The radar hasn't moved from its position after an alignment (bumper removal I get it), the only difference I can see is that the car drives straighter or wears the tyres less but not change the way the radar works.