Hello guys its not offten i get stuck but im puzzled to fuck atm.. I've just recently bought a corolla 1.3 4efe and ever since i got its had a very slight missfire at 33mph in 4th gear and when i change up in to 5th its ok for about 1min then starts missing again, its not a very bad missfire its more like a very slight judder but its starting to piss me off.. i've changed the leeds, plugs, dizzy cap, roto arm and its still doing it dont get me rong the car seams to be running alot better then what it was when i first got it as it had a slight missfire on tick over aswell but that seams to of gone but im still left with this slight judder at cuertain speeds.. Can anyone help please thanks in advance