i am under the impression that my Knock Sensor needs to be replaced, i have checked the ECU for codes but i don't have any. the last code i had was 0901 for right rear O2 sensor which was done. i had the car dynoed and the #'s as well as graphy was A W F U L so i am blaming the knock sensor but i had since had the ECU read twice and it has no 0304 code. i know that gas mieage may affected so does 22 MPG all highway miles sound about right for a 99 5speed with JWT popcharger and Warpspeed Ypipe. this is about speed averaging 80-100 mph . i am just hoping that this is my problem as to why my power is down.
is this normal or bad mileage, i also notice the car seems to be lacking in some power ....

 

My knock sensor is reported as non-working by the ECU, but I get 27mpg doing a mix of highway and city driving.

 

damn! i get only 19mpg and i thought it was okay!