A video of the noise could help..
I do know it's could be bad gas like a knock of some form.. of you can upload a short video it'll be helpful
2011 base Z | custom test pipes, stillen gen3, custom catch cans, LOVIN' IT
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2011 base Z | custom test pipes, stillen gen3, custom catch cans, Tein S-Tech springs, Whitle F sway bar, LOVIN' IT
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