Pontiac Repair: Acceleration Problems, honda acord, vacuum leaks


Question
Ok I have a 1994 Pontiac Grand Prix with a 3.1, the car has about 288,000 km on it. The problem as best I can explain it is it doest not seem to be accelerating very fast, During the first 2 or 3 gears its fine but at around 90-100 km/h it doesnt seem to have any kick what so ever.

Im not sure if im explaining this properly but my friends 91 honda acord with a 4 cylender accelerates alot faster at 90-100 than my 6 cylender.

So i am not sure would it be a clogged filter or the catalytic converter or a striped high gear. I know its an older car but it should still have some kick at the high end.

Not sure if i explained this properly but i tryed.

Second problem not sure if it would be related to the first but my car also consumes alot of gas more so than it probbly should im not too sure of the gas milage but it is pretty low unless i run premium gas in that case it seems to burn a bit slower.
thanks in advance.

Answer
i would change air and fuel filters and see if that helps.then check the fuel pressure at the fuel rail.if that all checks fine the cat may be stopped up.depending on the laws in your area you can have this removed or replaced.if that doesnt help the engine may just be wore out.bad compression or camshaft.i would also check for vacuum leaks as this will cause poor drivability.