Hey. I have a 94 accord lx 4cyl. A couple weeks ago i was driving down the road at cruising speed when all of a sudden my car made a sudden jolt, almost as if I had hit something. I checked my rear view and didn't see anything. Then all of a sudden my car's rpms gradually sunk down below 1000 no matter how much i hit the pedal. I got it towed back to my house and i cranked it up again to try and figure out what was going on. when i cranked it up it made this weird knocking noise as well as the rpm trouble. I switched my head for a new one figuring a valve was screwed up. That didn't fix it. Any ideas? Thanks.