the issue that i am currently having is when i start her up in the morning and head out to work it seems if i go over 4k rpm it makes a noise almost like a child pretending to shoot an automatic gun. I've just had the spark plugs replaced like 300 miles ago so that wasn't the problem. even after its warmed up the first really hard pull that i'll do to get the carbon buildup off it still makes the damn noise almost like its well struggling is the best word. any help on this issue would be great. thanks in advance everyone.

 

If it sounds like marbles in a blender, check out this thread:
https://www.rx8club.com/showthread.p...hlight=marbles

 

Ummm, don't rev the car over 4k when it is cold. The ECU will prevent this (think rev-limiter) with fuel-cut-out.

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