Slight Mis fire / jerk on part throttle

[schofield14]

car has idled rough since I bought it a month ago, had been sat as getting it ready for some track days. Today I toom it for a run and ran out of petrol, filled it up and now when hodling a constant speed or very little throttle input in any gear at any rpm it has a real slight misfire / judder. But not under load with more throttle so doesn't seem electrical. Reckon I've pulled dirt through? Any suggestions

 

[Laimface]

Had the same problem, got very bad for me! Mine was down to the two spark plug tubes in front of the oil breather getting full of watery oily s**t (breater gasket was leaking) meaning the spark was weak at low RPM, got new HT leads too as the old ones looked pretty burnt around the contacts. Another tip is to swap the pre and post cat lambda sensors over to see if there is any difference as it might be forcing open loop fueling due to a faulty front sensor which happened to me too!