My s2 has developed a misfire and the garage says its due to the 4th lobe on the cam being worn, can this be right? I don't know anything about engines so have no idea. I have had this car for two years and fitted a new cam when first got the car, that wore the 4th lobe so replaced it with a Kent cvs 35 cam which was second hand but fairly sure the 4th lobe wasn't worn that was only about 6 weeks ago.