I have a 97 f-150 v-8 4.6. It has started missing really bad at an idle. The trouble code says a miss on the #2 cylinder so i replaced the plugs and wires(it did this before and this cured the problem, about 2 years ago). It is still doing this but it is worse now. after we replaced the plugs and wires, we pulled the #2 plug and it was already all black and sooty. brand new plug. I think it might have a blown head gasket right on the #2 cylinder which is causing it not to fire. Any other thoughts or suggestions? Thanks much.

 

You may have a bleeding/leaking fuel injector causing your problem.