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Old 04-21-2024, 10:33 AM   #1
Lantzyt
 
Drives: 2021 Camaro LT1 Convertible
Join Date: Apr 2019
Location: Michigan
Posts: 27
23 LT1 Exhaust sound “turning off”

I drive around with the #15 fuse removed so the exhaust valve stays open all the time. I’ve had my 23 Camaro LT1 since 10/2022 and didn’t have any issues until about a month ago. It seems to be happening more frequently - every time I drive it now. Before, it only did it maybe a handful of times

Whenever I’m cruising along around ~2,000rpm there is a very quick “screech” noise and the exhaust sound turns completely off. The only way I can get the exhaust to make noise is if I give it some gas, and as I give it gas it sounds like a “schwoop” noise and the exhaust sounds like it opens back up and makes noise. I noticed it doesn’t matter the speed or which gear I’m in, it’ll always do it.

Anyone have this happen? Not sure if something is wrong or if this is typical from removing the fuse. I’ve removed the fuse in my 2021 LT1 and never heard this, same with my current one up until a month ago
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Old 04-21-2024, 12:52 PM   #2
Deacon Blues
 
Drives: 2024 Camaro 1SS M6
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Is it a manual or automatic? Reason I ask is because if it is auto and has AFM, it could very well be the exhaust valves opening/closing. I have a Silverado with AFM and when it goes between V8 and V4 mode, there is a slight screeching noise I traced to the exhaust flaps.


Not sure if that is what's happening in your case, but just food for thought.
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Old 04-21-2024, 01:57 PM   #3
Dynamical
 
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Drives: 2022 Camaro LT1 A10
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I agree with Deacon Blues. Def sounds like some kind of exhaust valves. I'm happy I went with non npp and have afm off so I don't have these issues.
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1998 Camaro Z28 A4 - Bolt-on
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Old 04-21-2024, 02:10 PM   #4
Deacon Blues
 
Drives: 2024 Camaro 1SS M6
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Location: Western NY
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I will say when I bought my Silverado it was the first time I experienced AFM and was a little unnerved. I thought that sounded like a bad u-joint. The AFM valves just seem to be noisy, and from talking with other 1500 owners, pretty common.
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Old 04-21-2024, 03:03 PM   #5
Lantzyt
 
Drives: 2021 Camaro LT1 Convertible
Join Date: Apr 2019
Location: Michigan
Posts: 27
Quote:
Originally Posted by Deacon Blues View Post
Is it a manual or automatic? Reason I ask is because if it is auto and has AFM, it could very well be the exhaust valves opening/closing. I have a Silverado with AFM and when it goes between V8 and V4 mode, there is a slight screeching noise I traced to the exhaust flaps.


Not sure if that is what's happening in your case, but just food for thought.
It’s an automatic
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Old 04-21-2024, 03:09 PM   #6
Deacon Blues
 
Drives: 2024 Camaro 1SS M6
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Location: Western NY
Posts: 172
Might want to see if this thread matches what you're dealing with: https://www.camaro6.com/forums/showthread.php?t=604428


Edit: this one too https://www.camaro6.com/forums/showthread.php?t=595008
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Old 04-21-2024, 08:17 PM   #7
Lantzyt
 
Drives: 2021 Camaro LT1 Convertible
Join Date: Apr 2019
Location: Michigan
Posts: 27
Quote:
Originally Posted by Deacon Blues View Post
Might want to see if this thread matches what you're dealing with: https://www.camaro6.com/forums/showthread.php?t=604428


Edit: this one too https://www.camaro6.com/forums/showthread.php?t=595008
Much appreciated
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