ok. im lost on this one. no engine light. runs fine when driving normal. however. under full throttle it sputters after 5k rpm. all 3 coils are sparking no problem so i dont think its icm or coils. ive herd a clogged up cat could cause this but i have a 3in catless down pipe. i put new ngk tr6 plugs on it about 8k miles ago. has anyone ever had this issue before? i have new plugs and wires on there way. if its not that what else could it be?