Hey my97323f 80,000 miles has developed misfire problem i think???? thats what youd call it not great with cars.

when i accelerate car will hesitate and then suddenly all power seems to come at once. The problem is not there all the time but seems a bit worse in wet weather and is worse at low speeds and best at high rpm's. ranges from slight hesitation to call not wanting to move. worse when under load.changed some parts and borrowered others from friends car (also97 323)to try find problem as im a student and cant afford main dealer costs

new spark plugs, new spark wires
borrowed airflow meter no better.
Tested on diagnostics machine 3 times no problems showing

any help much appreciated with this long running annoying problem. some one told me ignition coil may be problem??? [align=right][/align]