DaveGrun

My car has been getting terrible gas mileage and has has horrible low end acceleration. I checked the ecu and is was giving me 0304 (Knock sensor). My mechanic was telling me not to buy a knock sensor right away since he claimed that the computer gives knock sensor codes whenever there is a misfire or anything in the engine. He said most of the time the knock sensor code doesnt even mean you need a new knock sensor. Is this true?