[spta97]

I’ve read a lot about how quiet the X3m exhaust is for some and that most of the noise is the fake ASD.

I’ve found the exhaust to be fairly aggressive, even in comfort mode but especially in sport+ in my competition model.

As a result, I figured anything I was hearing was artificially generated by the ASD. I don’t care for fake, so I coded it off in Bimmercode but a lot of the sound was still there which would quiet when I pressed the exhaust button. I assumed that the coding did not work so I pulled fuse 218 yesterday.

To my surprise, nothing changed. The exhaust button still had an impact on exhaust volume. It still makes a difference in sound while in comfort mode and especially sport+.

Moreover, I still have the deceleration burbles/gurgles in sport+ while the button is lit - sounds which I convinced myself were fake.

Perhaps it is due to the competition model exhaust, but the button does seem to control the flap in all modes (granted I didn’t try regular sport) and makes an audible difference. The difference is huge in sport+ but noticeable in comfort as well.

I like having the option for both a quiet and louder exhaust note. I’ve never had burbles/gurgles but think they sound cool when wanted

As a PSA, I would not recommend keeping only the back windows open with the fronts closed as I did during testing. Even at relatively low speeds, the helicopter sound/pressure was so great I felt like my eardrum would pop lol.

[moff]

ASD and the exhaust flaps aren't really connected.

If you code out ASD the fake noise disappears then you control the exhaust flaps with the button. Basically the exhaust button does:

1. In efficient nothing
2. In sport some noise
3. In sport+ most noise

[spta97]

Originally Posted by moff

ASD and the exhaust flaps aren't really connected.

If you code out ASD the fake noise disappears then you control the exhaust flaps with the button. Basically the exhaust button does:

1. In efficient nothing
2. In sport some noise
3. In sport+ most noise

Everyone keeps saying it does nothing in comfort, but I can hear a reduction in sound if I turn it off.

Am I (not) hearing things?

[Waterbelly]

Originally Posted by spta97

Everyone keeps saying it does nothing in comfort, but I can hear a reduction in sound if I turn it off.

Am I (not) hearing things?

I'm with you. Definitely has an impact on comfort as well.

[moff]

Originally Posted by Waterbelly

I'm with you. Definitely has an impact on comfort as well.

The exhaust doesn't change in Comfort but ASD does, in the other modes the ASD is the same but the exhaust changes. Confusing I know.

[spta97]

Originally Posted by moff

The exhaust doesn't change in Comfort but ASD does, in the other modes the ASD is the same but the exhaust changes. Confusing I know.

I have ASD coded off and pulled fuse 218 because I thought it didn’t work

I still hear a noticeable difference in comfort mode with the exhaust button on vs off.

Do you have a comp model? I do - maybe that’s the difference?

[moff]

Originally Posted by spta97

I have ASD coded off and pulled fuse 218 because I thought it didn’t work

I still hear a noticeable difference in comfort mode with the exhaust button on vs off.

Do you have a comp model? I do - maybe that’s the difference?

Yeah Comp pack and also a European car so OPF's which mute the pair anyway.

[spta97]

Originally Posted by moff

Yeah Comp pack and also a European car so OPF's which mute the pair anyway.

Perhaps the lack of the OPF is the difference.

On my US build, the button impacts exhaust volume on all modes.

[Littleted]

Originally Posted by moff

ASD and the exhaust flaps aren't really connected.

If you code out ASD the fake noise disappears then you control the exhaust flaps with the button. Basically the exhaust button does:

1. In efficient nothing
2. In sport some noise
3. In sport+ most noise

Moff what did you eventually do to disable the exhaust button. Had mine 4 weeks, and I do think the HK is weaker in this than my old X3 I presume that exhaust button is effecting it somewhat

Did you just pull a fuse?

Thanks

[Transfer]

I don't notice any difference in comfort/efficient with exhaust button on or off. Sport and sport+ yes for sure big difference as comp exhaust is fairly loud IMO, especially in sport+.

[strohw]

Just start the car and let it idle in your garage. Open your door while in regular mode and stick your head out while you repeatedly hit the exhaust button. You'll be able to tell if there is a difference.