it only jumps when i have my foot on the gas it doesnt do it on take off just when im crusing along anywhere from 35 and up. as soon as i take my foot off the gas it quits. i was thinkin it might be my fuel filter cause i dont have a clue if it has ever been changed and the car has 250,000 miles

 

When was your last tune up?

 

yeha sounds like misfireing. fouled up plug or something

 

define tune up. i have changed the plug wires spark plugs and every fluid in the car thats about it

 

Is it an auto by chance?

I am not a big auto guy but I have heard of people having this problem when their trans fluid system is in need of a good professional flush.

 

yeah mine is an auto

 

You can try to diagnose it.
Get it up to speed where it does it and then put it in neutral and see if the engine still jumps. You could also do it while parked and bring the RPM's up.

Its not a sure fire way but it may help outline the problem.