Churchill

I love how PSE sounds, but the fake pops and crackling when lifting off the throttle IMHO are embarrassing. 991's aren't running poorly set-up carbs. It's just about the only thing on the 991 I don't like. There must be a way to program it out -- anyone know?

Dan Nagy

I am not sure if it is a program. From what I read, the pops and cackles help keep the catalytic converter hot to run more efficiently.

I'm not a fan of that aspect of the exhaust note either, but haven't had the opportunity to drive mine as it is still on the boat.

STG

Get the base (non PSE) exhaust??

The POPS and CRACKLES are not going away on the PSE. Not a programmable BMW fake sound. One cool feature in my opinion.

I hear the 991.2 is better for sensitive ears

Roosell

Why?!

spiderv6

Press the OFF button. That's the only choice.

Dangelus

The pops and the crackle are what make it awesome!

Roosell

Also, I suspect these sounds are not fake. I believe there is genuine after-burn happening in the exhaust system. Probably not necessary, but I don't equate that to fake.

Churchill

It's likely a fake-ish sound. You get pops like that (although they're more subdued) on early cars that don't have modern fuel injection and engine management systems. Driver lifts off the throttle, blocking the entry of air into the cylinder, leaving small amounts of unburned fuel, which then enters the exhaust and burns there, rather than inside the combustion chamber. Sort of like controlled, miniature backfiring. Pretty sure on 991's it's done by the ECU cutting spark on throttle lift, or the DFI injectors adding a little gas on lift. You don't hear anything close to that kind of noise on early 911's whose exhaust systems don't even have cats. I get why Porsche does it -- obviously most people like it. It's cool and sporty. I live in a city and would rather be able to program it out, and in general just don't go for contrivances like that.

991Esq

There is a way--program the individual setting in the sport chrono/mode switch to turn on the PSE and don't run it in the conventional sport mode. You get the PSE sound without the over-run sounds. Also, sport+ has no over-run sound either.

Dan Nagy

I can't seem to put my finger on the technicals, but it isn't fake at all. It just lets more exhaust note come into the cabin, but it also releases some drops of fuel to heat up the catalytic converters, and that causes the pops.

STG

What's the "embarrassing part"??

Do passengers and people walking down the street actually confuse the pops and crackles of PSE with flatulence??

Actually, it's a good way to pull it off incognito

Larry Cable

not that I am aware of, since Porsche programmed these "in" deliberately.

You *might* ping Cobb or one of their ProTuners (like Fabspeed or TPC) to ask if this is something their tunes can reduce or remove, otherwise you are stuck
being embarrassed!

kayjh

But according to answers to my question in another post, if the engine is above 3,000 RPM, there is no way to turn PSE off - the flap stay open. Don't know about the pops on deceleration though.

I guess if we don't like the noise, can avoid it by not ordering PSE

Larry Cable

The "pops and crackles" are not a function of the PSE exhaust (per-se) its a function of the throttle/fuel maps, its excess/un-combusted gas exiting the
cylinders and igniting elsewhere... its referred to as "lift-throttle overrun" as
I understand it.

not sure but a non Sport-Chrono (and thus non PSE?) car might not exhibit this.

JW911

By the way, if you listen very closely you can also hear some overrun popping when the car is not in sport exhaust mode. It is very muted. In fact hard to hear if you are not listening for it. But it is there.