Okay, my car has been acting odd for a while, i thought i fixed it with a fuel filter, but no, i was driving and went to pass a civic and in third gear at about 3750 rpm's it started knocking really loud and the car wouldnt go any faster, it acts like it isnt getting fuel or soemthing, im new to the rotaru thing so any help would be awsome, below are some of the things i have done to the car and replaced, maybe it will help someone let me know what is wrong with it.

Intake
Removed pre cats, staright pipe in place
Catco converter
dual hks mufflers
plug wired
ngk plugs
optima battery
new vaccum lines
kn oil filter
removed ac
fuel filter

 

At 3800, your car transitions from 2 injector to 4 injector operation. There is an issue here. Can you free rev above 3800?

 

yeah, it used to run great at high rpm unitll today, but if its not in gear itll go up to 8000 or higher if i let it

 

turbo or NA?

 

na with 155000 on it, but ive been told the motor is fine no smokeing or anything seels good

 

chcek and make sure your 5th and 6th ports work