NPP question
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Racer
Joined: Oct 2008
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From: winchester Virginia
NPP question
Hi, I have a 2014 m7 with npp. In the settings menu on the infotainment display there is a setting for engine sound management. If I open this setting there are 2 choices, auto or off. Anybody know what these actually do?
Thanks
Thanks
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The menu options are different in my 2015 and 2017, but... it should be 'auto' will change according to which mode you are in on the console dial (tour, sport, track) and off I would guess leaves it open most of the time similar to track mode.
Maybe someone else with a 2014 and these settings can confirm.
Maybe someone else with a 2014 and these settings can confirm.
Racer
Joined: Mar 2007
Posts: 430
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From: Church Hill, TN
I have a '17 GS. In that menu you can select which exhaust mode you want independent of driving mode. So you can select Track mode exhaust even if you are in Tour or Eco mode. There is also a setting called Stealth which closes the baffles and makes the exhaust sound "normal" if you don't want to wake the neighbors.
Safety Car
Joined: Jan 2014
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From: Walhalla South Carolina
The menu options are different in my 2015 and 2017, but... it should be 'auto' will change according to which mode you are in on the console dial (tour, sport, track) and off I would guess leaves it open most of the time similar to track mode.
Maybe someone else with a 2014 and these settings can confirm.
Maybe someone else with a 2014 and these settings can confirm.
Intermediate
Joined: Jun 2017
Posts: 43
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From: Merino Colorado
I have a 17 GS as well and mine works just like your's . I thought I needed a m2w switch and talked to my dealer and he showed me the trick to keep the npp open all times. Now someone will be along soon that will tell you I'm wrong, but I believe mine are open at all times. I can't hear them close and I don't have a camera that can ride under my car.
Team Owner
Joined: Aug 2007
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From: I live my life by 2 rules. 1) Never share everything you know. 2)
St. Jude Donor '11-'12-'13, '16-'17-'18
I have a 17 GS as well and mine works just like your's . I thought I needed a m2w switch and talked to my dealer and he showed me the trick to keep the npp open all times. Now someone will be along soon that will tell you I'm wrong, but I believe mine are open at all times. I can't hear them close and I don't have a camera that can ride under my car.
Drifting
Joined: Aug 2002
Posts: 1,519
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From: MI
The only way the exhaust stays open all the time is to pull the fuse of the use a mild to wild switch. In the software, you can set it so that the exhaust is in track mode regardless of the mode selected by the rotary switch. It's a testament to the programmers that many people think the flaps are open all the time in track. GM can not let them be open at all times due to the federal drive by noise standard. All modes close the valves at the prescribed federal test parameters.
How NPP works thread
How NPP works thread
I have a 17 GS as well and mine works just like your's . I thought I needed a m2w switch and talked to my dealer and he showed me the trick to keep the npp open all times. Now someone will be along soon that will tell you I'm wrong, but I believe mine are open at all times. I can't hear them close and I don't have a camera that can ride under my car.
Team Owner
Joined: Oct 2004
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Pulling the appropriate fuse is the only way to keep the valves open all the time. The fuse # varies from MY to MY, with 3 different locations. The M2W device is just a away of doing that electronically. Pressing the button adds or cuts power to that fuse. It's #41 in the 14, #42 in the 15-17, and another one entirely in the 18-19, which I don't recall.
Correct, on a '14 that there are only two settings. As someone said above, "auto" simply allows the mode dial to control the setting. "Off" keeps it mostly open, but not always. On post-14s, there is a setting for each mode as well as "Stealth." In all MYs, pulling the fuse is the only way to keep the valves open 100% of the time.
I personally don't care for that because with the fuse pulled or "unpowered" with the M2W, there is an annoying drone at highway cruising speeds with low rpms in the OD gears.
Correct, on a '14 that there are only two settings. As someone said above, "auto" simply allows the mode dial to control the setting. "Off" keeps it mostly open, but not always. On post-14s, there is a setting for each mode as well as "Stealth." In all MYs, pulling the fuse is the only way to keep the valves open 100% of the time.
I personally don't care for that because with the fuse pulled or "unpowered" with the M2W, there is an annoying drone at highway cruising speeds with low rpms in the OD gears.
Last edited by Foosh; Jan 7, 2019 at 12:14 PM.
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Team Owner
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From: I live my life by 2 rules. 1) Never share everything you know. 2)
St. Jude Donor '11-'12-'13, '16-'17-'18
Pulling the appropriate fuse is the only way to keep the valves open all the time. The fuse # varies from MY to MY, with 3 different locations. The M2W device is just a away of doing that electronically. Pressing the button adds or cuts power to that fuse. It's #41 in the 14, #42 in the 15-17, and another one entirely in the 18-19, which I don't recall.
Program the visor (if you have them) to control the M2W and that is pretty much a non issue
Last edited by KenHorse; Jan 7, 2019 at 06:07 PM.
Intermediate
Joined: Jun 2017
Posts: 43
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From: Merino Colorado
Not trying to be an *** or start an argument. I guess there is something I'm not getting.From the dic I have a choice of stealth, tour, sport, and track.Now there are only 2 possitions to the npp valve, correct, open or closed? When I am on sport or track their open . At any point while driving I can hit stealth and it goes quiet. In sport or track I never hear that. Sounds the same at any rpm, when I let off and down shift it burbles and pops.If they close I can't tell it. Is there something between open and closed?
Race Director
Joined: Apr 2017
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From: Virginia
Not trying to be an *** or start an argument. I guess there is something I'm not getting.From the dic I have a choice of stealth, tour, sport, and track.Now there are only 2 possitions to the npp valve, correct, open or closed? When I am on sport or track their open . At any point while driving I can hit stealth and it goes quiet. In sport or track I never hear that. Sounds the same at any rpm, when I let off and down shift it burbles and pops.If they close I can't tell it. Is there something between open and closed?
Safety Car
Joined: Jul 2018
Posts: 4,303
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From: Margate, FL
Auto changes the sound as you rotate the Drive mode selector between Tour, Sport and Track with each have a different sound. I think its a great feature so the car is reasonably quiet while cruising, but can growl and rumble louder when desired. By adding a Borla X-Pipe it just enhances the sound without being obnoxious.