Theta

freebird, if you're still reading this post, I will quickly break this down for you.

As you specifically labeled your post NPP, I will assume that you are concerned with only the NPP valves. The AFM valves (as others have been worried about here) were not part of your original question, and the options for removing the AFM feature are very straightforward.

To answer your question fully, though, without making you read through an additional 10 pages of information, the NPP valves are controlled by the CCM. This module attenuates the electronic valves based on selection criteria (the first being the ESM selector).

There are two caveats to the operation of the NPP valves in the 'OFF' state - the most important one here that is (apparently) being argued over is the FACT that the system has a tip-in based on TPS that actually does close the valves to a certain degree below a specific RPM. In most reported cases, the tip-in point is 1700rpm.

So, as you can see, even when the system is "off", it's not truly off. To permanently disable the electronic (unlike the C6's vacuum-controlled) valves from closing, the simple removal of Fuse 41 from the front engine compartment will do the job with no risk involved (contrary to the other misinformation you may have seen here). There is no error reported to the system, as these valves serve only to attenuate sound, and are not actively monitored for position. If the valves are removed, that's a bit of a different story, but that's an entirely different topic (that we do have a few threads about if you're so inclined).

Again, everyone lost sight of the actual question, and jumped straight to conclusions. This, however, was the information that the OP was looking for. Otherwise, he'd be asking about AFM, and not NPP.

Klyde

Theta:
What is your argument? I fully know that the fuse 41 will turn off the rear valves and I'm not disagreeing with that. The only time they come into play when turned off in menu is when they are needed to remove drone. I'm stating that there is no need to remove the fuse. It gets you so little it doesn't matter and what it does get you really don't want. Just turn it off in the menu. My statement that the AFM valves are for backpressure not sound control comes from the engineer who designed it. You know more them him? I'm just trying to inform everyone about the system as a whole. Pull the fuse if you want. Tell me what does it get you? Really! What do you gain other then drone below 1700 rpm? You should be the one to be up front with everyone. THERE IS NO REASON TO PULL THAT FUSE!!!

Theta

The OP asked how to leave the valves open at all times. Your very statement here shows that unless the fuse is pulled, the closure occurs at 1700rpm.

Does the original question ask about drone, or anything else? No, it merely asks "how do I keep the valves open?"... One man's drone is another's lust.

The reason to pull the fuse would be... oh I don't know... Oh yes! The answer to the original question!

Klyde

But that doesn't get him wide open all the time. He still has to deal with the AFM. The OP ask how to get that wide open sound all the time. If you look at my first response I stated that all he has to do is turn off NPP but that would not get him what he wants. He is still limited by the AFM valves which is what the rest of my original response was about. I also did not know if he has an auto or manual so I stated that an auto was even worst and would cause problem if you removed AFM valve control because it is active in every mode.

Theta

There's never been a mention of AFM, and no reason to bring it up based on the short original question. The real wonder I have is why that was brought up? I doubt he's wanting a wide-open sound in V4 - it's quite unpleasant. Not to mention, if he enjoys the 'wide-open sound', he would already be in Sport or Track (hence, V8) mode, out of the AFM quandary.

The question was "HOW DO YOU KEEP THE NPP FLAPS OPEN FULL-TIME?". Not "HOW CAN I BYPASS THE AFM FLAPS?"

I could understand bringing that up if the question was "how do I make my car stay loud all the time"? Them of course, you'd have to explain that AFM was there, the dangers (or at least options) of removing it, etc.

I went back and read my posts to see what set you off, and I'm still scratching my head. My only advice was to pull a non-monitored, non-essential fuse (not an AFM fuse), and you accused me of giving dangerous information? A bit rude, not to mention factually incorrect.

Now, if I would have gone wild telling him to start ripping wires apart and bringing out a clippers... Sure, you'd have a point.

But, since that was never the case... I'm sensing you're the type of person who is going to have to be 'right' to end this discussion. Your first post in this thread was one of FUD, so I probably should have kept quiet and not corrected you in the first place.

...So now that the question has been factually answered, I'm moving on. Best of luck, freebird!

lastcowboy

nav, screen, settings . pick auto or or off , off for open all the time
drive in sport
drive in track

AFVETTE

As an innocent bystander to this issue (I don't own a C7 yet) and have been reading any/all post on the unique operating features of the C7 and or differences between the C7 and C6 and this thread has been an education.

I appreciate the open and honest debate on display in this thread and at least for me I'll be a smarter C7 owner.

thebiglittledog

I had the mild to wild in my 13 GS had it on the wild mode 99% of the time, love the drone if thats what you call a bad *** sound of the Corvette, So when I picked up my C7 and after reading many threads posted on this subject as Theta has stated I pulled my fuse 41 and and love every minute of the drone, also when I pull up to light all the other cars around seam to like the drone as I have had many many many people ask me to rev her up so they can here the DRONE, Theta thanks for all your onsite to your knowledge of the working of the C7. Klyde it may be a sad day but you were wrong on this.

Elite275

Theta nailed it. Flaps open all the time...pull the fuse. Otherwise, even with the controls set to off on the screen the flaps will close and tip in at the 1700 rpm mark. My tolerance could be high since I've had exhaust systems that drone terribly, but I find the drone minimal with the fuse pulled and low RPM cruising.

That's what is great about it simply being a fuse to pull. Yank it and drive the car around. If the drone is bad for your taste when the RPM's drop then just pop fuse 41 back and you're good to go.

Like many others, I'm still hoping for someone to figure out to give us the true mild to wild activation and control that we were used to on the C6. Once the headers go on mine my fuse will go back until we have a solution so I'm courteous to my neighbors early morning or late at until...until then they remain open all the time.

JerryU

Can I do as I did with my '08, and install a simple switch using an Add-A-Circuit to replace fuse 41 so it is bi-passed when desired?

Elite275

Unfortunately, there is nothing like that available like that yet but people are still experimenting. It's a lot more complex due to the pulse signal being passed.

c5eddiem

Klyde,

I would suggest that you read this thread: (in it's entirety)

http://forums.corvetteforum.com/c7-t...ck-result.html

Then, you may realize that Theta has the precise answer to the original question, and a solid understanding of the "pull the fuse" reasoning.

I would suggest a "you're right!" response to him, primarily because he (and Xp800) have it down precisely!

Jerry,

"Can I do as I did with my '08, and install a simple switch using an Add-A-Circuit to replace fuse 41 so it is bi-passed when desired?"

Yes. I'm experimenting with a simple way to do it. I started by buying a new fuse cover so I could cut a hole in it for the switch. Controlling the valves is tricky, but pulling the fuse (or switching off the circuit, as you ask) is simple, and it works. Some of us are at the "best way to do it" stage...

Ed

ps. Klyde, I pulled "ol' 41" and the difference is significant!

Harry2

Would not installing the Mild to Wild controller in a C7 allow you to "pull the # 41 fuse" via the controller just as the C6 did?

I have a C7 in route for delivery this week and have already pulled out my Mild to Wild controller from my C6, question, will it work on my C7?

Walt White Coupe

From what's been detailed here, it seems that the C6 Mild to Wild system should also work on a C7. If not, why not?

1500cc

What's the difference between pulling a fuse, versus adding a switch that either closes or opens the circuit on demand?

GRG

Theta if you find yourself going out to the backyard to scream bloody murder a couple of times a day, I understand. Glad, even impressed you are able to answer questions cool and calmly. I hope you find a way to make the c7 work like a c6 with mild to wild as I miss that sound.

Glen e

Well done theta......

Harry2

I have asked the supplier of the Mild to Wild controller if it can be used in the C7. I am sure if it is usable he will let us know quickly as there may be lots of new C7 business for him and the manufacturer of this device.
I agree that if the #41 fuse can be simply pulled to obtain the "Wild" sound, then an electronic controller doing the on/off switching should work too.

lgodom

I'm wondering if the Mild to Wild controller I had in my ZL1 would work. I don't have a C7, so I can't try it, but all it does it mimic pulling the fuse.

Klyde

C5Eddiem:
I have read that article in its entirety many weeks ago. Also last month when I went over 500miles break-in I pulled the fuse on my C7. Unfortunately I have an automatic. Went for a spin after popping the fuse and was rewarded with a low speed drone whenever I held a constant speed. The auto just hits the wrong RPM’s at the wrong time. When I got onto the highway my car went right intoV4 mode and it sounded terrible. Turned around and headed home and in my neighborhood, while in Sports Mode doing 35 mph it kicked into V4 mode again and at that moment I decided to put the fuse back in.

Before my first post AFVETTE mentioned AFM and asked about tuning it out. Millpond stated that for an auto just use Sport or Track to illiminate AFM. MKR1966 got it right by saying with auto your screwed. I looked up the OP’s stats and he shows a 2009 as his vette so I didn’t know if he has an auto or a manual and he doesn’t mention the menu so I didn’t know his level of use with the C7. So in my first post I mentioned turning NPP off in the menu but go on to mention that you still have AFM and its two valves to deal with based on my earlier experience. I explain that, with an auto, AFM is active in any mode and do to its function cannot be removed without re-tuning which voids your warranty. Later Theta, a tech contributor, made the statement that the AFM valves were for sound control which I knew to be false because of statements made by GM engineers. At no point did I ever state that removing the fuse would not deactivate the NPP system. My statement was it is not necessary to do so. Actually it is quite annoying if you have an automatic like I do and works a whole lot better leaving it in and turning it off in the menu. My statement to Theta about being careful with promoting this as a solution was because there are many different technical levels of people on this forum and some may not fully understand what he is suggesting. He took this as an insult which it was not meant to be but to each his own.

After removing the fuse weeks ago I can only think that you who swear by it must certainly have manual transmissions. I could not tolerate it for more than the ten minutes it was pulled. As Theta states “What’s bad for one man is blessed for another”. My thoughts are there is no need to pull that fuse.