MK1 Focus 1.6 Zetec stuttering issue
 

Hi all
I have an issue with my Focus where the car sometimes stutters/hesitates slightly when accelerating from low speeds, mainly in second gear.
I changed the coil pack around 6 weeks ago but it's still doing it.
What I have noticed is it doesn't do it all the time but more often than not it's when I have slowed down and gone into second and attempt to accelerate again.
Also, it doesn't seem to happen when the engine is first started/cold for the first couple of miles.
Anyone any idea what may be the cause as it's beginning to pee me off!
Cheers