S3 8V exhaust drone

[JimboBlue]

Hi All,

Quick query regarding exhaust noise, I have had a '67 plate S3 (first registered in Jan 2018) for around 11 months, the car is great but there's one thing that bugs me which is that I find the exhaust to be quite droney/intrusive between 2-2700k, it's the same whatever driving mode I’m in and because it happens at relatively low revs it's irritating when pulling away from junctions etc, it's actually worse or more noticeable with gentle acceleration because the engine stays in that rev band for longer, it's also annoying at motorway speeds as you get the drone when gently accelerating to pass slower cars.

I have an OBDeleven and have checked that the exhaust flaps are active which it says they are so I assume they must be connected, I wonder if it could be a faulty valve or is there something else the previous owner could have done to alter how the exhaust valves behave? Any help gratefully received!

 

[AlS3BE]

Sounds like a resonator delete.
have a look and see if you can see a Centre box in the exhaust.

 

[JimboBlue]

Sounds like a resonator delete.
have a look and see if you can see a Centre box in the exhaust.

The previous owner had fitted a res delete but Audi refitted a new centre box before i collected the car

 

[BCS Nige]

We produce an anti drone resonator kit that might help
Cheers
Nige
Powervalve
01744 610244

 

[JimboBlue]

We produce an anti drone resonator kit that might help
Cheers
Nige
Powervalve
01744 610244

Thanks Nige, I'm hoping there's something that can be resolved with the current set-up as I can't believe it should sound like this as standard, we shall see!

 

[AlS3BE]

Get a long stick and check the valves through the tailpipes. At start up all is open but if you park up in comfort then exhaust valves should be closed so the stick should hit something.
I have a 2018 factory standard and there’s no drone whether I’m in comfort or dynamic. It is slightly louder in dynamic but not really droning.

 

[JimboBlue]

Get a long stick and check the valves through the tailpipes. At start up all is open but if you park up in comfort then exhaust valves should be closed so the stick should hit something.
I have a 2018 factory standard and there’s no drone whether I’m in comfort or dynamic. It is slightly louder in dynamic but not really droning.

Thanks, i'll give that a go, i wasn't sure if you could access the valves as in various photos i've seen of the rear silencer the valve actuators look like they're very close to the silencer, i'll see if i can find a bendy stick!

 

[AlS3BE]

Thanks, i'll give that a go, i wasn't sure if you could access the valves as in various photos i've seen of the rear silencer the valve actuators look like they're very close to the silencer, i'll see if i can find a bendy stick!

Have a peek and see if the electrical plugs on the valves are connected. I’ve seen some blanking plugs for the connectors so that they might appear working in vcds/obd11.
I would also double check the dealer has fitted the box back in as I’m sure out the factory it’s one piece up to the mid pipe so manifold to cats to centre box is a very expensive piece from Audi.

 

[JimboBlue]

Have a peek and see if the electrical plugs on the valves are connected. I’ve seen some blanking plugs for the connectors so that they might appear working in vcds/obd11.
I would also double check the dealer has fitted the box back in as I’m sure out the factory it’s one piece up to the mid pipe so manifold to cats to centre box is a very expensive piece from Audi.

I did check under the car and they have definitely replaced the centre resonator, I'll have a look at the connectors to check they're connected properly. Given that the the previous owner had removed the resonator I do wonder if they might also have altered the operation of the valves somehow

 

[AlS3BE]

I did check under the car and they have definitely replaced the centre resonator, I'll have a look at the connectors to check they're connected properly. Given that the the previous owner had removed the resonator I do wonder if they might also have altered the operation of the valves somehow

If you have obd11 you should be able to check if the flaps have been disabled Or maybe check the apps and see if you can see the status.

 

[JimboBlue]

If you have obd11 you should be able to check if the flaps have been disabled Or maybe check the apps and see if you can see the status.

I have used the app in OBDeleven to disable and then re-enable the flaps but it didn't make any difference, I also had a quick look at the long coding option and as far as i could tell the option for exhaust flaps enabled was ticked. I wonder if OBDeleven would be able to tell if a different device had been used previously to disable the flaps, like VCDS for example

 

[AlS3BE]

I have used the app in OBDeleven to disable and then re-enable the flaps but it didn't make any difference, I also had a quick look at the long coding option and as far as i could tell the option for exhaust flaps enabled was ticked. I wonder if OBDeleven would be able to tell if a different device had been used previously to disable the flaps, like VCDS for example

Long coding will be the same regardless what tool you used to see it. apps in obdeleven might be different.
Cant really think of anything that could cause drone. Even in dynamic with flaps open mine doesn’t really drone. Only other extreme is the cat has been gutted.

 

[nothingness]

Check the actual plugs. I unplugged mine and when I sold the car I couldn't get them to fit back into their plugs so I just left them unplugged and taped them back up. It made the same amount of drone that you describe, basically any time it was on boost it droned. Also, my car had all the characteristics of a resonator delete but looking under it, it had the stock resonator. I think someone previously gutted it.

BCS do a rev3 resonator delete now with an actual box so it should get rid of ALL drone with your valves unplugged.

Another way to tell if your valves are unplugged, do they all soot at the same rate or only two pipes? If unplugged they will all soot at the same time. This looks far better IMO than just 2 out of 4 dirty tips.

Not nano grey your car is it? lol

 

[JimboBlue]

Check the actual plugs. I unplugged mine and when I sold the car I couldn't get them to fit back into their plugs so I just left them unplugged and taped them back up. It made the same amount of drone that you describe, basically any time it was on boost it droned. Also, my car had all the characteristics of a resonator delete but looking under it, it had the stock resonator. I think someone previously gutted it.

BCS do a rev3 resonator delete now with an actual box so it should get rid of ALL drone with your valves unplugged.

Another way to tell if your valves are unplugged, do they all soot at the same rate or only two pipes? If unplugged they will all soot at the same time. This looks far better IMO than just 2 out of 4 dirty tips.

Not nano grey your car is it? lol

Mine's Ara Blue so not your old car! The plugs are definitely connected and the inside pipes do soot up more than the outer ones, it's as if the valves are opening earlier than than they should when under any load. It's due a service soon so will ask Audi to check when it goes in. Thanks for all the replies and suggestions

 

[AlS3BE]

Mine's Ara Blue so not your old car! The plugs are definitely connected and the inside pipes do soot up more than the outer ones, it's as if the valves are opening earlier than than they should when under any load. It's due a service soon so will ask Audi to check when it goes in. Thanks for all the replies and suggestions

valves opening and closing is a bit more dymanic/variable to conditions. It’s not just at certain revs and it opens. Last time I looked at this on live data it opens and closes 1 or 2 valves depending on load, revs, which drive select mode it’s on and if the engine is warm. this is why dsg farts don’t always work.

 

[JimboBlue]

valves opening and closing is a bit more dymanic/variable to conditions. It’s not just at certain revs and it opens. Last time I looked at this on live data it opens and closes 1 or 2 valves depending on load, revs, which drive select mode it’s on and if the engine is warm. this is why dsg farts don’t always work.

It wouldn't bother me if it only happened in dynamic or when pressing on but it's the same in comfort, whether warm or not and because it happens at lower revs it becomes intrusive, I feel like the S3 should be pretty refined unless you don't want it to be!

 

[nothingness]

I have read about people who have had the valve opening / rpm ratios changed. So it's possible I guess. Unless you buy new you have no idea what the previous owner did. Some people have launched their cars thousands of times, some people bounce them off the limiter when cold..it really is a lottery .

 

[JimboBlue]

Does anyone know whether the exhaust valves should be closed with the engine off - I have bought a cheap little endoscope camera for my iPhone and I can see that with the engine off both valves are still open, before switching the car off it was in individual mode with engine in comfort, I would have thought the valves should be closed?