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skibuddy
10-05-2012, 02:41 PM
So; I have had my new A6 for two weeks now and I am totally bemused by the situations under which the Stop Start conditions are met. Slip the car into neutral, let up the clutch and the engine doesn't stop. The symbol appears in the display crossed out. Now; I have read the manual and: the engine is warm, the aircon/heating isn't going mental etc etc etc. As far as I can tell, there should be no reason why the engine shouldn't stop. It does occasionally, but seems totally random. More 'start' than 'stop'. Given it takes effort to put the car in neutral and take your foot of the clutch, it is pretty disappointing when it doesn't kick-in. Pretty soon I guess I will give up trying. Much to the detriment of the environment I guess. What have others experienced?

MFGF
10-05-2012, 03:10 PM
Mine doesn't stop before it's up to temp, but once warm it stops pretty much every time - even with headlights, wipers, heated mirrors on and a/c on auto (all four zones). It can be a little bemusing in stop/start traffic - it no sooner stops than I dip the clutch to get moving again, so it's on and off incessantly.

I had one occasion where I stopped and it didn't recognise the car was stationary - the A symbol didn't appear at all and the engine kept running - but otherwise it's done exactly what I expected.

Cheers!

MF.

Timothy Nathan
10-05-2012, 03:21 PM
Mine sometimes doesn't (mine's automatic) but mostly does. I haven't worked out the algorithm.

zollaf
10-05-2012, 04:43 PM
i wonder how long starter motors will last for someone that regularly drives in heavy traffic ??

Timothy Nathan
10-05-2012, 04:45 PM
I'm hoping for 4 years 10 months.

skibuddy
10-05-2012, 10:21 PM
After a bit of experimenting on my way home tonight, it seems that if I turn off the air con unit it worked every time, even when the engine was cold.

MFGF
10-05-2012, 11:14 PM
i wonder how long starter motors will last for someone that regularly drives in heavy traffic ??

I have started to wonder about that too! :) There is a handy button on the dashboard to disable the stop/start function, or you can just keep the clutch pressed. I tried a little experiment on my journey home from work to see if I could fool it. As I was approaching yet another set of red traffic lights on the A56, I knocked the car into neutral, let up the clutch and coasted to a gentle stop. The engine stayed running while the car was in motion, and the moment it came to a halt it obediently switched off. The boffins at Audi obviously predicted there would be muppets like me trying to find different ways of fooling the system, and designed it accordingly :)


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Guest 2
10-05-2012, 11:18 PM
Very true, the A4 done this, didn't really like it at the start but got use to it and started to coast up to lights then it just died.

Although I did forget I was driving a manual and not an auto and forgot to clutch to start again!


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skibuddy
17-05-2012, 07:47 AM
Three weeks on from picking up the car and Stop Start still seems completely random whether it kicks in or not.

MFGF
17-05-2012, 07:11 PM
Three weeks on from picking up the car and Stop Start still seems completely random whether it kicks in or not.

I tried out the heated seats the other morning (they are HOT even on 2!!) and noticed that stop/start didn't activate. If you go to the Eco screen on the DIS, you can see which items are drawing power. With just A/C listed, the stop/start seems to do exactly as I'd expect.

Cheers!

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skibuddy
19-06-2012, 04:13 PM
I thought I was imagining that Stop Start was in some way related to how hard I pressed the foot brake when coming to a stop but the post by Nealeb on this post Hill assist? (http://www.vwaudiforum.co.uk/forum/showthread.php?125899-Hill-assist) seems to confirm it. Can anyone else confirm or refute this?

Timothy Nathan
19-06-2012, 05:00 PM
I am not sure that I understand your question in full, but if you approach the stop with ever lightening foot pressure (which is the normal way of not getting a jerking stop) Stop Start won't stop the engine. If you then press the brake harder (or stop with harder pressure in the first place), the engine stops. If you lift the pressure, even a little, the engine restarts and won't stop until you have moved.

If you use Hill Assist, then the car won't slip backwards in the moment between the brake being taken off and the engine restarting, so, in my opinion, the combination is essential if you are not on the Fens.

skibuddy
19-06-2012, 06:18 PM
My observation is (independent of Hold Assist) that if you stop with light braking, slip into neutral (mine is a manual) and raise the clutch, then the engine does not stop. However, if you stop with a firm press of the break peddle, slip into neutral and raise the clutch, then the engine does indeed stop. Depressing the clutch again restarts the engine. I think this this concurs with what you have just described.

MFGF
19-06-2012, 06:39 PM
My observation is (independent of Hold Assist) that if you stop with light braking, slip into neutral (mine is a manual) and raise the clutch, then the engine does not stop. However, if you stop with a firm press of the break peddle, slip into neutral and raise the clutch, then the engine does indeed stop. Depressing the clutch again restarts the engine. I think this this concurs with what you have just described.

Hmmmmm. My experience is a little different. With the car stopped (whether after gentle braking or fierce braking) if I put it into neutral and let up the clutch, the engine stops. It doesn't seem to make any difference how hard I press the brake pedal. What brake pedal pressure does seem to influence is the hill hold function. If I stop very gently with the car on a near-level surface, the hill hold doesn't engage. Pressing the brake pedal hard (even after the car has stopped) will then engage hill hold.

Cheers!

MF.

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skibuddy
19-06-2012, 06:55 PM
This was the original post from Nealeb that struck a cord with me, although I haven't come across this in the manual.

"Start/stop seemed slightly hit-and-miss on my new A6 having gone for a drive yesterday after collecting it. Reading the manual (after the event, of course!) it seems that s/s looks at how hard you apply the brakes - press hard and the engine will stop, light press - just enough to stop it rolling? - and the engine stays running. Subtle point but one that may be useful if you keep edging forward in a queue."

Timothy Nathan
19-06-2012, 08:19 PM
My post was about the automatic, and doesn't apply to the manual. So you can ignore it!

nealeb
20-06-2012, 08:27 AM
Interestingly (well, it interests me...) there seems to be two different brake pressure/pedal depression points. The first, with lighter braking, will trip hill assist to come on, and the second, with harder pressure, will activate start/stop. As a result, I typically turn off HA when I am manoeuvring (backing into a parking space, for example) as I eventually realised that it completely fouls up slow-speed control. Slight pressure on the brake could often cause HA to come on, which needs a bit of throttle to make it release, which means a bit of a lurch backwards towards that barrier looming up in the reversing camera. Turn off HA and it's much easier, although remembering that you can release HA with the brake switch can help. Having stopped with a light touch on the brakes but enough to bring on HA (traffic lights, for example), you then need to press a bit harder to activate SS. This is all with an S-tronic gearbox, so not quite sure how it translates to a manual.