NPP fuse
07-12-2018, 06:55 PM
#2
Team Owner
Yes it is fuse #87, I pulled it on my 2019 no issues great sound.
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vettez51zo6 (07-13-2018)
07-12-2018, 08:17 PM
#4
Le Mans Master
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vettez51zo6 (07-13-2018)
07-12-2018, 09:02 PM
#5
Melting Slicks
Even in track mode the flaps adjust/ close, pull the fuse they are always open. Haven't tried in my 17 yet fuse #in the 17 anyone?
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vettez51zo6 (07-13-2018)
07-12-2018, 09:39 PM
#6
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See second page of explanation from FSM below:
That is just about as clear of a statement that GM can make about the valves. No need to pull the fuse.
Bill
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07-13-2018, 08:02 AM
#7
Team Owner
^^^^ Well you and your interpretation of the manual are wrong. The NPP valves DO NOT Stay open 100% of the time they will close at certain rpms.
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07-13-2018, 09:39 AM
#8
Drifting
Correct even in track mode the valves on my car also did not remain open 100% of the time. I chose the mild/wild option however over just pulling the fuse.
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vettez51zo6 (07-13-2018)
07-13-2018, 10:41 AM
#9
Melting Slicks
The "see note above" is missing from his picture. I know from experience in my Z51 it makes a difference. I have not tried in my Z06 so leave that to those who have.
Last edited by cheapthrills; 07-13-2018 at 10:42 AM.
07-13-2018, 02:28 PM
#10
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Bill
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07-14-2018, 02:46 PM
#11
Instructor
Montana Bob
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07-14-2018, 03:18 PM
#12
Safety Car
A camera setup would prove it. Wish I had a gopro.
07-14-2018, 03:19 PM
#13
Hello corvette friends, I just bought a 2019 zo6 and in the rear hatch is a clear plastic bag inside the bag are cold air brake ducts my dealer told me they won't install them because they said the ducts are for track use only. any thoughts on this subject ???
07-14-2018, 05:53 PM
#14
Team Owner
The dealer is correct.
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07-14-2018, 06:52 PM
#15
Le Mans Master
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They are open at idle in Sport and Track and not tour just like the FSM says. If I drive the car in Tour mode they stay open all the time from idle at a traffic light all the way to max rpm at wide open throttle. They are open at very low rpms just running along at 50 mph in 6th.
Bill
Bill
07-14-2018, 09:12 PM
#16
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Do you have somebody riding behind your car checking the valves while you are driving? I can hear my exhaust and when the engine switches to V4 there is a noticeable cut in exhaust noise ( which matches what the note referenced in the FSM indicates). Put the car in Tour Mode where it doesn't switch into ECO mode and the exhaust is open all the time. If you have an A8 where it switches to V4 in Tour Mode what you might be hearing is the valves closing when it swtiches. Pulling the fuse just makes it worse if that is the case. The exhaust sounds terrible in V4 mode if the valves are open.
Bill
Bill
07-14-2018, 09:26 PM
#17
In normal driving without Performance Shift when I let off the throttle in Sport mode, the valves will close. When your not heavy on the throttle when you let off approaching a traffic light, I believe they close some, if not all the way. I feel like they are programmed more to throttle position. However, when your on it in Performance Shift they’ll stay open under engine braking. I have an A8.
07-14-2018, 10:13 PM
#18
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In normal driving without Performance Shift when I let off the throttle in Sport mode, the valves will close. When your not heavy on the throttle when you let off approaching a traffic light, I believe they close some, if not all the way. I feel like they are programmed more to throttle position. However, when your on it in Performance Shift they’ll stay open under engine braking. I have an A8.
Bill
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Lyn Go Fast (07-15-2018)
07-14-2018, 10:35 PM
#19
I don’t do track mode too much because of the ride. It makes sense that the valves should just be wide open in track. My theory is I had both valve actuators fail. When the valves were closed in tour mode the valves made a hideous clicking noise. When the valves were open, no noise. So when I drove around in the different modes I could tell when they were in the closed position. In sport coasting off throttle the valves were closing because the noise was there. I didn’t try track.
07-14-2018, 11:13 PM
#20
Drifting
Maybe there's something with the M7 and A8s... My car is procharged, cammed, tubes etc... In track mode you could CLEARLY hear the car close the valves. While crusing at certain RPMs. There's no mistaking or need for some one to be looking down the damn pipes to verify.