No npp!
Thread Starter
Heel & Toe
Joined: May 2022
Posts: 21
Likes: 9
From: Elida, OH
No npp!
Recently purchased a 2012 Grand Sport, I noticed that the mufflers do not have a vacuum switch installed.
Did they make units without the NPP feature? I'm thinking someone replaced the original equipment muffers.
The replacement mufflers aren't Corsa or Borla they appear to be factory installs.
What say you?
Did they make units without the NPP feature? I'm thinking someone replaced the original equipment muffers.
The replacement mufflers aren't Corsa or Borla they appear to be factory installs.
What say you?
Racer
Joined: Jun 2020
Posts: 258
Likes: 28
From: Ontario, Canada
Do they have the valve, but no actuator, or no valves at all? I'm not sure if all GSs came with the NPP feature (other members may be able to chime in), but it is possible someone installed a louder exhaust, and then a subsequent owner reverted to a non-NPP stock setup.
Drifting
Joined: May 2015
Posts: 1,525
Likes: 391
From: Martinez CA
I have a 4LT '12 Grand Sport, without NPP.
If you want to check what the car came with from the factory, check out the build sheet. NPP is the option code.
I wound up using some ZR1 cans, and installed an after market vacuum kit with the remote control.. Very happy with it so far...
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3rd Gear
Joined: Oct 2021
Posts: 3
Likes: 1
NPP RPO but standard mufflers
I have a similar question. I just purchased a 2012 GS 4LT. The RPO sticker shows NPP as an installed option but the car has standard OEM mufflers. Are there any other physical indicators I can look for on the car that will give me a definitive yes or no for the option? If the car came with NPP I want to put it back on. Thanks
Pro
Joined: Jun 2022
Posts: 749
Likes: 254
From: Florida
I have a similar question. I just purchased a 2012 GS 4LT. The RPO sticker shows NPP as an installed option but the car has standard OEM mufflers. Are there any other physical indicators I can look for on the car that will give me a definitive yes or no for the option? If the car came with NPP I want to put it back on. Thanks
3rd Gear
Joined: Oct 2021
Posts: 3
Likes: 1
3rd Gear
Joined: Oct 2021
Posts: 3
Likes: 1