Misfiring on acceleration.

Can anyone give me advice on this issue?

I have a 1998 4.6 HSE auto that is misfiring/hesitating on hard acceleration. e.g kickdown at 60 mph it drops a cog starts to take off hit's around between 2500-3000 and then it seems something is holding it back feels almost like the old "wild spark" effect you used to get with a knackered dizzy cap. It does this both on Petrol & LPG. It starts first time everytime whether hot or cold.

I'm thinking of replacing plugs leads and coil pack but would obviously like some expert advice before shelling out on parts,


Many thanks in advance.

MAF possibly

Stripped the top end down today to replace inlet manifold gasket and rocker cover gaskets aswell as replace spark plugs and leads, No. 2 lead fell out of coil and no.s 5, 7 & 4 were green on the ends where they fi into the coil as well as burning on the connection end of spark plugs 4 & 6. all put back together took for a drive and goes like a scalded cat. Happy days.raise:

Well done - got there in the end!