I have a 95 3.4 and it wasnt accel. that fast, it was kind of cutting out almost. so i changed the fuel filter when i bought it thinking that would fix it. It helped it some i guess but it was still doing it rather bad so i put new spark plugz in it. That helped it much givin me a about several mpg. But it seems to still be hesitating and kind of cutting out some. Could it be wires? it has 111,000 on it. ALso when i get after it it has a thumping sound up by the air filter by the front wheel what the hell is that?

 

check timing

 

try revving it (by hand) with the hood open, if it cuts out at a certian rate of throttle each time it may be throttle position sensor, if it backfired through the intake valve it could be timing,
is your gas milage normal?
if its just being sluggish your cat could be plugged

not throwing any codes?

try taking out the 02 sensor and drving the car around
if the car gets faster it could be the cat, or it could still be timing spitting fuel and burning the o2

 

ok, ill give it a try, but what about that thumping noise?

 

that thumping noise could be it backfiring through the inkate valve, you will know it because it will scare the crap out of you

and you will see the intake shake

 

what does the o2 sensor look like and were is it at?