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Popping noise??

3728 Views 2 Replies 3 Participants Last post by  g-wizzelwhat
Hi everyone.
I put the loud magnaflow cat-back system on my 09 g8 gt and i have a popping noise when i let off the throttle in the active select mode. When the engine is holding back it pops a few times when i downshift. I was just wondering if this is normal for this system or if I might have a small leak? I like to drive in active select mode so it stays in v-8 mode, sounds better ;).
This is the first car i've had that I had to use the cruise control to keep from speeding.Awesome!!!!!!!
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I am a terror in my new GXP as far as speeding goes. It pops between shifts with the stock exhaust, just as you describe on your GT.
what you are experiencing on the gt is a lack of back pressure and will eventually cause the vavle seats to "burn" then you will lose compression, but that may not happen for a few years. all that is happening is when you let off the throttle the raw unspent fuel if being dumped in to the header/ exhaust mainfold and igniting there. if you were to have the car tuned it may help or find a way to add some back pressure to the exhaust system. as for the gxp if it is still stock you may want to have that looked at.
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