I replaced the cam follower a few months back, some of the coating had worn off the top but it was in otherwise reasonable shape. Symptoms have been present prior to the follower being replaced.
I have had one instance of a misfire on cylinder 3, I haven't yet checked the coil or the plug, but I have also been unable to repeat the symptoms, although I haven't driven the car especially hard.
As the fault codes I was logging were to do with fuel rail pressure, could a misfire cause that (and not show a fault for a misfire)? I have only had the engine light flash once after the misfire, not after any other occasion.