A8 Parts Forum

A8 Parts Forum (https://forum.a8parts.co.uk/index.php)
-   D3 - Everything Else (https://forum.a8parts.co.uk/forumdisplay.php?f=64)
-   -   ACC Switch off (https://forum.a8parts.co.uk/showthread.php?t=13613)

Audidothat 17th November 2017 08:26 AM

ACC Switch off
 
Hello all

Unless on a motorway at 3am I find the auto distance function a royal pain. It is far more intrusive and ‘brake happy’ than ACC systems I have had on previous cars.

Is there a way it can be disabled so that the car has basic cruise control?

Goodness knows what it is like to follow an Audi with ACC but the way the car over brakes it must be creating a concertina affect behind me.

ACC is often quoted on here as a must have option, personally i’m not so keen.

Conquistador 17th November 2017 11:22 AM

I've wondered the same before, whether it's just a case of simply coding it out somewhere and having it as a classic cruise control. I've driven quite a few cars with full ACC, not just collision mitigation system, and it's nowhere near the best. Range Rover's and Mercedes Distronic are the most refined in my opinion.

The D3's ACC picks up a car in front from a fair distance away but is useless at tracking cars around slight bends on major roads and it will drop anchor at the most inappropriate times. I appreciate it isn't to be heavily relied on but it would be a nice feature on long journeys if it was more refined, although it will be good for resale value.

HPsauce 17th November 2017 12:25 PM

Interesting discussion. +++

The ACC on my Volvo generally works really well, though is probably a later variant compared to the D3 version. I use it almost all the time. It does occasionally lose track of vehicles on quite windy roads with strange results, and also over-compensates with excessive braking for those turning off into side roads or driveways, though a dab on the accelerator sorts that out.
It also seems to behave quite intelligently when you change lane. :cool:

Like the D3 (I think) you can adjust the following distance easily and the detection range (or indication of vehicle in front) seems to vary according to speed.

There is no option to revert to "classic" cruise control and I expect Volvo would say that would negate the safety aspect anyway so wouldn't allow it. There are additional permanent anti-collision systems as well though they only operate at lower (not motorway) speeds, up to about 35mph IIRC.

Audidothat 17th November 2017 02:33 PM

I find even the closest detection range setting still too far away.

For me the worst symptom is if a vehicle pulls out in front of me to overtake another vehicle, instantly halving the ACC detection range, but still at least 20-30 (approx) metres in from of me.

My car instantly brakes heavily to return to the preset detection range causing everything to brake behind me. Why can’t it just come of the gas? Why brake? Maybe something to do with closing speed......

Trouble is the overtaking vehicle has completed its overtake but the ACC is still yet to accelerate again, leaving me at least 100 metres further back!

Anyway the suggestion of a quick dab on the brake myself may solve this for me.

Conquistador 17th November 2017 02:58 PM

ACC from that era is quite rudemental compared to modern systems. Newer Audi ACC systems even have two radars (they look like black fog lights) to create a 3D map of the vehicles ahead, which improves the depth perception. But I agree a quick dab of the brakes works well, just enough to flash the brake lights, and cuts the throttle when someone pulls out to overtake.

The four preset 'distances' are time rather than actual distance. So distance setting 1 will be a completely different distance to the vehicle in front if you are traveling at 20mph or 120mph, but the time gap between two points should remain constant. Braking force and acceleration vary through distance 1-4 also. The time intervals are listed in the manual somewhere and can't be tweaked but they can in newer models +++

daandaman 18th November 2017 08:46 AM

Does anyone know of someone on some forum that has been decompiling equipment of vag cars? My friends are doing this with bmw ecu's. I've thought about it so often that we need to adjust the minimum speed and also the adjustable 'distance' settings. Id happily test it if we can update the firmware to say 0km/h and all distancr/time settings to a third of what they are now

Turbo Tony 25th November 2017 10:15 AM

In the scenario when someone pulls out in front of me within the detection distance, I do the opposite. When I see them beginning to move into my lane, I put my foot on the gas pedal. A second or two later, the ACC detects the new car and wants to brake but realises I have my foot down, so flashes the distance control LED to let me know I'm in manual mode. Finally, the car will eventually either accelerate away or will return to it's original lane and I get off the gas and carry on using ACC.

The advantage of using the gas pedal rather than the brake pedal is that you don't have to re-engage the system after the manoeuvre is complete.

HPsauce 25th November 2017 10:36 AM

Quote:

Originally Posted by Turbo Tony (Post 135207)
The advantage of using the gas pedal rather than the brake pedal is that you don't have to re-engage the system after the manoeuvre is complete.

Good description, I do exactly the same in my Volvo and it works well. +++

Audidothat 25th November 2017 12:22 PM

I’ll give that a go!

By the way, good to hear from you again Tony!

Turbo Tony 25th November 2017 01:25 PM

Quote:

Originally Posted by Audidothat (Post 135219)
By the way, good to hear from you again Tony!

Thanks! It's good to be back! :)


All times are GMT. The time now is 01:04 PM.

Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.