check ur fuel pressure,if it falls off predetination will occur or spark knock.also check ur mass air meter if there is debris on it your pararemeters will go in the dirt.when u remove it make sure its cool, spray it off w carb or brake cleaner non chlortinated wont leave a film.have a pro do ur tuning its always worth the coin,timing and or fuel is most always the culpritt.let me know!