SL400 2016 Sport+ Mode - Grating noise and smoke

[Karaokek]

Maybe someone has had a similar problem.
Relates to 2016, May, SL400 – 8,000 miles on clock.
I have had the car for last 4 weeks.
Have experienced the following problem yesterday and today.
Yesterday, whilst doing a hard acceleration in sport+ mode had a momentary grating sound (I liken it to the sound of an old skiffle washboard) – eased off the accelerator, everything OK. Drove the car rest of the day, no more hard accelerating, everything OK.
Today – same thing, but as I came to a halt, seconds after, the car was enveloped in light grey smoke. Smoke quickly went – I switched to comfort mode and carried on without a problem.

Spoke to Mercedes, who advised that it may be a stone caught in the brake pads – this could cause the noise and the smoke.
My concern is that this has only happened when hard accelerating – not braking and only when in sport+ mode.

Any thoughts or suggestions would be much appreciated.

 

[renault12ts]

My thoughts...not a stone.

Second thoughts...get it in to the dealer for investigation.

 

[Karaokek]

Have to say I'm thinking on same lines - thanks for your reply.

 

[MarkACLS]

Probably not the brakes, but do be aware that stability control uses both the throttle and the brakes and it can be that under heavy acceleration or high lateral load that the car may be independently braking a wheel.

I often get, after a spirited drive, more brake dust on the rear wheels, than i do on the fronts - even in Sport handling mode.

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