Hey Guys, I have a standed issue EF Fairmont, and its having a bit of trouble, ill try my best to explain, i start it in the morning and it drives perfect, then half way to work it wont idle, runs on 5 cylenders, then it clears up abit and then it does it again, if i turn it off for a little and drive it again it drives fine for a bit, then it plays up again, and some days its perfect all day

, ive had it serviced, plugs ect, but i havnt done the leads? its been comp tested and water pressure tested and comes up sweet! so its not the head gasket, its frustrating, some days its perfect all day, others it will be a dog, and it seems whenever it is at my mechanics it runs great so he cant pin point whats wrong with it lol, leads? ive heard coil packs can do this?? i thought it would do it all the time?? or dirty injectors? but again, wouldnt it do it all the time? hope someone can help

thanks evryone!
Rick