[RobM2]

When idle, whether M Exhaust Sound is on or off, I notice the tone of the exhaust changes ever so slightly when I engage the clutch: the rumble gets slightly deeper (it sounds better imo).

I can't tell if this is the ASD or actually the engine/exhaust changing. Of course idle would change slightly when the clutch is engaged vs not, but this sounds different, probably ASD?

Does anyone else notice this? It is barely perceptible but super weird.

[Digitalprty]

I notice this too. Don’t know what it is. Doesn’t bother me.

[Resoelg]

Most definitely a different sound with petal down and I have ASD coded out. Better sound with the valves open too. I can't tell you why.

[RobM2]

Glad it isn't just me.

I'm not bothered by it but I'd love to know what it is — super weird if it isn't ASD. I'd prefer it always made the deeper sound.

[Good 4 2 reasons]

The exhaust valves, while at a stop, only open when the clutch pedal is depressed.

[Geighty7]

Valves opening slightly for exhaust/engine flow. Not ASD.

[M_Power Rob]

Originally Posted by Good 4 2 reasons

The exhaust valves, while at a stop, only open when the clutch pedal is depressed.

Unless you have a valve controller with them set to open...

[Squidget]

or toothpicks

[Dave07997S]

Idle tone changes as fuel is added a tad to help with clutch engagement. It's not the exhaust valve. You can see your fuel consumption go up a bit when you push the clutch in.

[BradMX5]

This happens in my Miata

[Sleeper]

Originally Posted by M_Power Rob

Unless you have a valve controller with them set to open...

My Dahler controller doesn’t override this. Clutch out in neutral, Sport +, exhaust valves set to full open all the time via the Dahler controller, and the exhaust gets much quieter until I clutch in.

[stashstein]

Yeah it's not the exhaust, it's idling up to help you not stall. Same as basically every other manual car.

[youloze]

Agree with the above. It's 100% not the valves or ASD. I have ASD coded off and my valves are open at all times. Definitely for clutch engagement from a stop.

I think it's fun to quickly clutch in and out at a light to make my wife roll her eyes.

[Mr. Hankey]

Originally Posted by stashstein

Yeah it's not the exhaust, it's idling up to help you not stall. Same as basically every other manual car.

This. These cars have anti-stall. Let the clutch out with no gas, it doesn't stall and car will idle at 4 MPH, Gear Change assist on or off. So if you have rough 1st gear engagements, let the car do it.

[daddyjaxx]

While getting some exhaust clips yesterday, I noticed that the turbos spool up when revving while the clutch is pressed and in first (compared to revving in neutral). I've got a non-res AA EL and SST controller.