drvai

Just got the car. I have the S tronic and E diff. Sometimes, when slowly accelerating (e.g. a parking lot) I hear a "clack" and I can actually feel it in the pedals. Will obviously take it to the dealer but I rather have an idea of what might be. Or is it normal?

Ash83

RS5? S5? A5?

does come at the same time the auto lock doors kicks in?

superswiss

That's normal. It's the hill start feature. I'm not sure why it sometimes clacks if you start on a flat surface, but if you start on a hill the brakes hold for a couple of seconds to give you enough time to change over to the throttle before the car starts rolling down the hill.

drvai

Thank you all for the answers. Is an S5.
Good though about the auto lock, but I have it disabled.

Good thing it seems to be normal. Any way to trigger it and confirm is that?
I guess try it on a uphill?

superswiss

Yep, find a steep enough hill and do a hill start.

drvai

Will be tough to find a steep hill here. Will try in a parking garage. Realy hope tha is that becuase I really avoid having the car in the dealership.

Could not find anything in the manual about start assist. Just hill descent control. Mine is a 2014.

drvai

Im a bit confused now... The manual doesnt say anything about "start assist". Looked everywhere and does say:
"when starting from rest the breaking force of the parking break is not released until sufficient driving force has been built upon the wheel".

This must be what Im experiencing. But the parking break led is never on... Does it always activate when the car is on P and off?

superswiss

No, the parking brake does not automatically engage in P. But if you engage it, the parking brake automatically disengages if you are wearing your seat belt and apply enough throttle.

Hill Start is not described in the manual as far as I remember. It's just something that needs to be there on an S-tronic car, otherwise it would be rather undriveable on hills as you would have to remember to manually engage the parking brake every time you start on a hill. It's not like with a manual transmission where you can hold the car with the clutch on a mild gradient or do a handbrake start. Hill Start engages automatically if you stop on a gradient of 3% or more and it holds the car for about 2 seconds.

BTW, Hill Start is not to be confused with Hill Hold (not available on US cars). Hill Hold needs to be manually engaged and holds the car indefinitely whether you are on a hill or flat surface. On a flat surface it avoids the creeping forward if you take the foot of the brake.

I felt the same way as you the first time I felt it simply pulling out of my garage, but after driving some hills, I accepted it as normal.

drvai

Got ya'.
So for whatever reason it engages even on flat surfaces.