Stop/Start causing car to jump forward

[jamesRS]

Hi All,

I haven’t seen this topic before, so apologies if I’ve missed it.

I have a FL 15 car and have noticed that intermittently when in traffic and the stop start is working. When starting to release the brake, the engine fires up, but it appears the car decides to engage the clutch also. This is a problem on 2 fronts.
1 – the car starts to launch forward meaning without hitting the brakes hard I would rear end the car in front!
2 - I end up looking like a complete idiot who cannot control his RS6!

Has anyone else had this issue? It appears to me to be a software flaw in that it’s allowing the clutch to engage whilst the revs are high when starting. Is there a fix that I should get my dealer to apply?

Cheers,

James

[Leo-RS]

Not sure I fully understand your dilemna?

Start/stop is activated on the brake pedal, if you release the pedal, (without popping it into park) then it will fire back up again, you would normally be in drive, so the clutch is engaged and the car would naturally move forward?

This is how its supposed to work is it not? It's certainly how mine behaves. If you don't want it to stop/start, either switch it off, or apply lighter brake pedal pressure.

[mat776]

I have MY16 FL (September) and the behavior is different

Brake Apply - gently = HHA - harder = activates start/stop (stops)
Brake Release - does nothing
Accelerator - gently = starts engine - harder = releases HHA and moves forward

It works really well as long as you don't hit the throttle too hard to disengage HHA and start engine and jump forward violently. Its easy to dab the throttle to start the engine without releasing HHA and press again to go.

Different from other Audi's I've had, where as you describe, engine re-start is on brake release, which I found a bit annoying as I had to keep my foot on the brake pedal at slow lights if I didn't want the engine to fire back up straight away.

[doodlebug]

There's muddling of two things here.

As above there's hil hold assist and there's start/stop. You can have either or both engaged or not. Start/stop is dependant on other staff like climate control and engine temp.

If you step of the brake with start/stop enabled but no HHA then it will engage drive and start to apply power. It shouldn't jump forward as you describe, but if you step right off, then that's pretty much what I'd expect.

[jamesRS]

Sorry if I wasn’t clear. But the behaviour I’m experiencing is not what I would call normal.

Imagine starting a manual car whilst in gear with the clutch engaged. The car launches forward. This is what it does.

Most of the time, the engine starts when releasing the brake without any issue, then I can press the accelerator and we move off. But it’s the few times when it jumps forward that is my issue, it’s a massive safety fail in my opinion, and if not quick enough to press the brake again, it would easily hit the car in front

[W8PMC]

Surely the clutch/s are engaged until you press the loud pedal so if it's jumping forward then you have a fault.

I can't recall the process in a C7 RS6 as has been over a year since i drove one, however in my car (as doodlebug says) once up to Temp etc. with Start/Stop on when i come to a stop & the brake pedal is past just a very gentle application the car will switch off (this gentle brake application can bypass stop/start if required). If i remove my foot from the brake the car starts but no gear in real terms appears to engage, if i press the loud pedal the car takes off, however if i lightly tap the loud pedal then creep mode is engaged & the car will gentle/slowly creep forward or backwards depending if the car's in drive or reverse, however the car will not move at all unless i apply some level of pressure to the accelerator.

[doodlebug]

Sorry if I wasn’t clear. But the behaviour I’m experiencing is not what I would call normal.

Imagine starting a manual car whilst in gear with the clutch engaged. The car launches forward. This is what it does.

Most of the time, the engine starts when releasing the brake without any issue, then I can press the accelerator and we move off. But it’s the few times when it jumps forward that is my issue, it’s a massive safety fail in my opinion, and if not quick enough to press the brake again, it would easily hit the car in front

Time for a trip to your helpful Audi Service Centre.......turn it off in the interim if you're concerned. Ideally you'll be able to demonstrate to them.

[superlightr]

Sorry if I wasn’t clear. But the behaviour I’m experiencing is not what I would call normal.

Imagine starting a manual car whilst in gear with the clutch engaged. The car launches forward. This is what it does.

Most of the time, the engine starts when releasing the brake without any issue, then I can press the accelerator and we move off. But it’s the few times when it jumps forward that is my issue, it’s a massive safety fail in my opinion, and if not quick enough to press the brake again, it would easily hit the car in front

try it without the hill hold being on. I found that when this was on then when you pressed the accelerator it would want to overcome the inital braking force and jump forward as it overcame the hill hold.

So ive got the hill hold button off (just below the hand brake button) and when waiting in traffic as others have said gentle braking the car stays on, harder press and the engine turns off. Dont have any jumping when pulling away like this

[Paulm]

I don't use hill hold, mine is very smooth and does not jump forward, it will move forward as its an Auto that's what they do but very gentle and slow.

[MartayMcFly]

Not sure where HHA plays into all this, but my FL does a mix of both. The stop/start fires the engine back up when I'm about half way back off the brake pedal, but the car doesn't lurch forward. It doesn't even roll forward until I press the accelerator (or if it does it's an imperceptible amount that makes no progress before I'm on the other pedal deliberately moving ahead).

[Markp]

Mine jumped forward on restart in traffic today for the first time in 6000 miles - scary!

[boff]

Can we VCDS Stop Start off? I absolutely hated it on my weekend loaner, simply the engine is too big for stop start, and the rocking of the car when it did it was frustrating. The only solution I could find apart from pressing the button was to drive on the edge at all times so that the car never elected to use it.....

[doodlebug]

This isn't normal. It's absolutely fine, it does what you'd expect it to.

[MikeFish]

Can we VCDS Stop Start off? I absolutely hated it on my weekend loaner, simply the engine is too big for stop start, and the rocking of the car when it did it was frustrating. The only solution I could find apart from pressing the button was to drive on the edge at all times so that the car never elected to use it.....

Boffmeister. I used vcds to invert mine rather than permanently disable it. So when I start the car it is off (and button light off). If I decide for some reason one day to turn it on I can just press the button and it comes on and button light lights up. But when I restart the car it will be off again. You can off course just permanently disable too.

[boff]

Can we VCDS Stop Start off? I absolutely hated it on my weekend loaner, simply the engine is too big for stop start, and the rocking of the car when it did it was frustrating. The only solution I could find apart from pressing the button was to drive on the edge at all times so that the car never elected to use it.....

Boffmeister. I used vcds to invert mine rather than permanently disable it. So when I start the car it is off (and button light off). If I decide for some reason one day to turn it on I can just press the button and it comes on and button light lights up. But when I restart the car it will be off again. You can off course just permanently disable too.

Nice one Mike!!! for me it was completely un-necessary like stupid.... erm I have a 600bhp v8 and i want to save fuel with it turning off for the seconds i spend at a red light, or a junction - infact that was the worst - queuing for a roundabout. it is daft on this car, and with the size and mass of the engine it is disturbing!!!