Johniorio4

Hey guys, I recently pulled the fuses 41 and 32 to keep the exhaust baffolds open all the time (as recommended by someone on this forum.) In his post, he says he does exactly this and gets no CEL. I did it, and immediately after, it came on. I tried putting the fuses back in and resetting it, but it stayed on. My question is, am I hurting the car by keeping these fuses out, or should I just ignore the CEL, because in reality, what harm could pulling a couple exhaust fuses have on the engine?

Thanks!

Papas02C5

Disconnect your battery for about a minute or two then reconnect. This will reset everything and get rid of your CEL... I have my fuses pulled with no CEL issues.....

This is a very helpful thread:
http://forums.corvetteforum.com/c7-t...=npp+fuse+pull

Johniorio4

Ok man will do. Also, what fuses do you have pulled? Just want to be sure 41 and 32 are correct.

Papas02C5

Those are the correct fuses. I have both pulled. I reinstall #32 when I do long road trips because I usually run in Eco Mode on the Interstate. #32 controls the V4 valves and it sounds like crap with the fuse pulled in V4 mode...
Do you have an A6 or M7. If you have an A6 I would not recommend pulling #32 unless you drive it in Sport Mode all the time....

Johniorio4

I have an m7 that I always drive in sport mode

dovervold

I have #41 out, and no CEL's after 2,000 miles, and it is a M7. Why would we want to pull out #32. I never use ECO mode, so I would assume the V4 valves will always be open. Is that not correct...

Johniorio4

I suppose that is correct.
Now I feel like an idiot! Haha

xp800

Pulling #32 is the cause of the CEL.

My thread here was where I and others figured it all out:

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

FKING1

Don't mean to muddy things, but, in my 2105 with Z51 the owners manual has fuses
#32 for one valve & 42 for the other. #41 is shown for headlights.
I pulled the 2 & started it up with no codes.
Will see after driving a while.

FKING1

Put them back, caused check engine. Disconnect Batt to reset light.
Damn!!

RussM05

If you go to the center infotainment screen> Settings > Drive Mode> Engine Sound Management> Off. I believe that keep the NPP valves 99% of the time? What am I missing here?

RonC7

Use the link in post #8. Good summary in the first post in the first post in the "Fuse..." thread. Read the whole thread for details!

xp800

This is from pulling the AFM fuse 32. This is the cause of the CEL.

The NPP fuse is 41 (2014) or 42 (2015). Pulling this will not cause a CEL.

And thank you for being one of the first to call attention to the NPP fuse change for 2015!

Please see:

https://www.corvetteforum.com/forums...ck-result.html

xp800

All explained below. Not disagreeing too much with the 99% though.

For many they may never notice ESM Off vs. NPP fuse pull if automatic. For manual it's easier to notice.

https://www.corvetteforum.com/forums...ck-result.html

xp800

Papas,

You can probably same some hassle and just leave AFM fuse 32 in all the time.

From what's collectively been discovered, there's no reason to ever pull the AFM fuse 32 for manual or automatic cars. The only things that does is cause a CEL and make V4 sound like crap. The AFM valves remain open all the time except in V4 mode, so forcing them open doesn't make anything louder or better. The NPP valves are the only way to change the V8 sound, and Engine Sound Management on/off or NPP fuse pull are the only 3 ways to tailor the behavior.

bob guzzy

The light will go out after a few run cycles don't worry about it I have been through that already.

Find the correct fuse by looking at the diagram on the lid of the box or looking in the manual.

You only pull one fuse # 41 or 42 the other is for the flaps for a AFM sound if you have a m7 you won't worry about these unless you drive in E mode