swap the plugs around fella i might be able to have a peek for you in the week as i work in chingford fella if you want
2 heads are better than one lol
are the readings all even when you checked compression
cant be injecters if the prob remains when you swapped them over
could have the wroung signal from the ecu going to that cylinder
no way you could of mixed them up by any chance is thier dude