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Old Dec 29, 2019 | 04:15 PM
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Default NPP question

Can anyone tell me if the npp actuator valve on my npp exhaust is vaccum or electric. The valves quit working, and I can only find electric connections on the butterfly.
My Vette is a 2016 Z51. Thanks for any info.

Valves are stuck open, which is ok, but since we installed the catless xpipe and had to move and reinstall the exhaust, the valves quit woking.
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Old Dec 29, 2019 | 06:14 PM
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Originally Posted by Ramrover2006
Can anyone tell me if the npp actuator valve on my npp exhaust is vaccum or electric. The valves quit working, and I can only find electric connections on the butterfly.
My Vette is a 2016 Z51. Thanks for any info.

Valves are stuck open, which is ok, but since we installed the catless xpipe and had to move and reinstall the exhaust, the valves quit woking.
Electric
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Old Dec 29, 2019 | 06:21 PM
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Originally Posted by Ramrover2006
Can anyone tell me if the npp actuator valve on my npp exhaust is vaccum or electric. The valves quit working, and I can only find electric connections on the butterfly.
My Vette is a 2016 Z51. Thanks for any info.

Valves are stuck open, which is ok, but since we installed the catless xpipe and had to move and reinstall the exhaust, the valves quit woking.
There's a few options to turn them off. Did you check exhaust driving mode? might be set to track mode, or check the fuse?

Last edited by phantom1; Dec 31, 2019 at 02:19 PM.
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Old Dec 30, 2019 | 05:38 PM
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Originally Posted by Ramrover2006
Can anyone tell me if the npp actuator valve on my npp exhaust is vaccum or electric. The valves quit working, and I can only find electric connections on the butterfly.
My Vette is a 2016 Z51. Thanks for any info.

Valves are stuck open, which is ok, but since we installed the catless xpipe and had to move and reinstall the exhaust, the valves quit woking.
e
Electrical...check the fuse if they are stuck open...check connections at the pipes near the valves...look for burnt wires, disconnected wires etc....highly unlikely, but don't overlook the obvious and most simple possible solutions.If power is lost to the circuit, they will stay open like you have described.... A device called Mild -2 - Wild can be bought at a reasonable price that pretty much replaces the fuse/ interupts the fuse right at the circuit and allows you to control the NPP with a keyfob or better yet your garage door visor buttons if you have them and you will need two of them..one for valves shut and one for valves open...I have mine set on stealth on my dash and other controls in sinc with the mIld2wild for mild and track mode for mild2wild wild mode.....also have an AWE x-pipe that eliminates the rear pup cats for better flow and a bit more agressive sound...no code alarms either as the rear pup cats are not monitored by the car's computer. hope this is helpful!
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Old Dec 31, 2019 | 12:45 PM
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Mild to wild has two modes, one mode disables the factory computer controls with the valves defaulting to fully open all the time and the other mode restores the system to normal computer controlled operation with the valves opening and closing per your selection of the drive mode, engine speed and whatever other parameters Chevrolet has programmed into the car.
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Old Dec 31, 2019 | 01:52 PM
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Originally Posted by Guard Dad
Mild to wild has two modes, one mode disables the factory computer controls with the valves defaulting to fully open all the time and the other mode restores the system to normal computer controlled operation with the valves opening and closing per your selection of the drive mode, engine speed and whatever other parameters Chevrolet has programmed into the car.
Basically the same thing I had said but better described in this post....
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Old Jan 2, 2020 | 03:01 PM
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Originally Posted by limuzinshchik
what kind of fuse to remove that would disable them
Google Mild 2 Wild for C-7 Corvette...and find install instructions on line...the fuse that they remove to insert the Mild 2 Wild is the one that will, when removed, keep the NPP valves open at all times. The Mild 2 Wild if you purchase it does as I have and also Guard Dad have described...(you don't need this device if you want to run with the NPP's open all the time...just pull the fuse out)....Hope this helps!
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Old Jan 3, 2020 | 08:07 PM
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Originally Posted by limuzinshchik
where is the fuse and turn it off
Please read my previous post....it tells you where to find it...and it explains the whole process.
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