[thomaswatk]

I love the open exhaust sound so I pulled fuse #51 as suggested. On my '16SS it isn't open "full time". If I am cruising at a given speed ( doesn't matter what speed) and not accelerating at least slightly, the exhaust closes. When I give it a little gas I hear a slight "pop" and they are open as long as I am on the gas a little. They seem to close anytime I am not accelerating a little bit (or a lot) so, for me, they aren't open "full time". They are never open when decelerating. It is much better than Is there a way to keep them open all the time ?

[NobleSS]

Sounds like you are hearing the AFM valves opening and closing while its going from V8 to V4 and back to V8 mode. By pulling fuse #51 there is no power to the NPP valves, so they can't work.

[driven2exceSS]

Originally Posted by NobleSS

Sounds like you are hearing the AFM valves opening and closing while its going from V8 to V4 and back to V8 mode. By pulling fuse #51 there is no power to the NPP valves, so they can't work.

+1 agreed. Hate the AFM's... try the "Range Device", preferably the 8.6, or the current version available to date. Other option is forego the warranty and get a tune to eliminate this non-sense to stay in V8.

[solarstingray]

mine works fine with the fuse pulled, always open,

and I just put in the afm range device it works flawless so far, no more afm

[init4fun]

Like other have said. AFM is what you're hearing.

Annoying as all hell.

[rap47]

I have the fuse pulled and the Range 8.6 version installed. Exhaust open all the time and V-8 all the time.

[aronSlusa]

Originally Posted by thomaswatk

I love the open exhaust sound so I pulled fuse #51 as suggested. On my '16SS it isn't open "full time". If I am cruising at a given speed ( doesn't matter what speed) and not accelerating at least slightly, the exhaust closes. When I give it a little gas I hear a slight "pop" and they are open as long as I am on the gas a little. They seem to close anytime I am not accelerating a little bit (or a lot) so, for me, they aren't open "full time". They are never open when decelerating. It is much better than Is there a way to keep them open all the time ?

I have this same issue, and pulling the fuse did not keep the valve (before the exhaust) open all the time; still closes at cruising speed.

The tuning shop my cars sitting at right now didn't understand what valve I wanted to make sure was tuned out/ off as they went though and tuned it.

[awpti]

Range device sucks -- drops a CEL after 1-2 days of use. Had multiple firmware flashes, now I just have 100 bucks of plastic in my glove compartment.

[solarstingray]

Originally Posted by awpti

Range device sucks -- drops a CEL after 1-2 days of use. Had multiple firmware flashes, now I just have 100 bucks of plastic in my glove compartment.

is it the newest version of It ?

[thomaswatk]

what is a range device and where do you get it ?

[bdavies11]

Originally Posted by thomaswatk

I love the open exhaust sound so I pulled fuse #51 as suggested. On my '16SS it isn't open "full time". If I am cruising at a given speed ( doesn't matter what speed) and not accelerating at least slightly, the exhaust closes. When I give it a little gas I hear a slight "pop" and they are open as long as I am on the gas a little. They seem to close anytime I am not accelerating a little bit (or a lot) so, for me, they aren't open "full time". They are never open when decelerating. It is much better than Is there a way to keep them open all the time ?

Try driving in manual mode (assuming you have the A8) and see if you notice a difference. Like others have said, if you have the correct fuse pulled, it is probably the AFM kicking in and out, not the exhaust valves. It should almost never go to V4 mode when driving in manual mode, even when cruising with light throttle.

I drive in manual mode almost all the time with the fuse pulled and it may kick into V4 mode when I first start the car up and am driving carefully out of my neighborhood. Then once I give a quick stab of the throttle or downshift, I'll get that "pop" that sounds like the exhaust valves opening (which is really the AFM) then it goes back to V8 mode and and stays there no matter how gingerly I operate the throttle from there on out. There's really no need for a range device or software to disable AFM you just need to keep it in manual mode.

[thomaswatk]

Thanks for all the replies. I'll try the manual mode, which I seldom use unless I'm in the mountains, and see how that works.

[GroundhogSS]

Aren't there separate AFM valves in front of the cats separate from the NPP valves that will still open and close?

[grampa_ss]

Originally Posted by GroundhogSS

Aren't there separate AFM valves in front of the cats separate from the NPP valves that will still open and close?

Yes. Completely different. I have fuse 51 pulled too. The NPP valves always stay open. But those !@$# AFM valves I hear when it goes into V4 mode. It's a muffled sound..sounds like the car is "bogging". I think if I delete the sound tube it won't be as noticeable.