my car missfires

[m42nut]

hi there im new to this site, i own a 1990 318is its well looked after.and i have this missfire problem. iv replaced all the rubber pipes under the bonnet, serviced it, new leads, plugs, filters, reconditiond the injectors and i just cant seem to find the problem. dose any think they can sugest what my prolem is? its getting annoying spending so much money on a problem that isnt beeing cured thanks

[JoshyC]

try replacing the distributor cap and rotor arm if you havent already

[asmith88]

as above exactly what happened to my mini, youd be surprised the difference it makes