Well...I've come to ask for some advice (planning on taking my car to the mechanic next week on my days off to find out what is going on). My 10 year old 1996 Honda Civic LX has some SERIOUS hard engine knock whenever I slow down and begin to accelerate (just before I begin to accelerate it knocks). Happens just about every time. And yes, I've even tried different grades of gas with no results. Also, it vibrates incessantly on the freeway and feels like it's falling apart. Just over 80,000 miles. One other thing I've noticed: whenever I am passing the speedometers that are placed on the road from time to time (those giant ones with large numbers) I notice that my speedometer is consistently five MPH below the actual speedometer reading on the units placed on the road. Is this normal?