Exhaust flap continually open findings

[Iain]

I do find when driving sometimes in manual mode that it doesn't pop and bang when going down the box - have to select S again, then put it back into manual for the shotgun pops and bangs the Milltek makes.

[Scotty C]

I agree...this new car seems to please itself when it throws out the pops and bangs whereas i could control it perfectly in the Pre FL...

[wrekka]

I def noticed this between my pre fl with milltek and my PE model with milltek.

[tartan_rob]

Much more V8 rumble and great in high gear, low revs.....a real V8 burble.

[Bit_evl]

Please excuse me if this has been covered before.

How do they make the car do the pop, bang, crackle stuff on the sport mode changes ?
In the old pre-cat days I would have expected over rich mixture on the webbers and cam changes causing unburnt fuel escaping through to the hot exhaust.

With a cat on the exhaust I cannot see this being good for it. Knowing Audi don't want to pony up for a lot of expensive new cats under warranty I cannot see them doing this.
Can any of the more knowledgeable members enlighten me ?

[Foxy]

I thought the whole pop, crackle thing is witchcraft, is it not just all synthetic?

[Bit_evl]

Thats the point. Many cars use the audio system to pipe in nicer engine noise but I don't think the RS6 is a new enough platform to have this cheap trick. I don't doubt it is ECU managed but how and what is it ?

[MikeFish]

It is new enough for noise through speakers but doesn't have it. The pops and crackles are ECU generated and I though it was just by overfueling. Isn't this how MRC create it on the B7 and C6?

[Foxy]

Thats the point. Many cars use the audio system to pipe in nicer engine noise but I don't think the RS6 is a new enough platform to have this cheap trick. I don't doubt it is ECU managed but how and what is it ?

It's certainly new enough as I had it on my 2012 991S, the sound was piped into the cabin but the pops on the overrun may well have been done by over fuelling as Mike says.

[wildbore]

As said above by Bit-evl, there is a catalyst in the exhaust. Unburnt fuel can destroy the catalyst so this seems an unlikely method of inducing the pops and bangs.

[Iain]

Engine management system trickery - the techies will be along to answer - its unburned fuel... not anything else.....