Re: 156 judder / stutter
first thing to do is remove the water or oil (usually oil, any that you spill when filling the engine collects on cylinder1).
then refit the coil and fingers crossed it wont happen again. the water or oil allows the coil to earth to the head, which cuts the spark to 2 out of your 8 plugs, leading to poor ignition on 2 cylinders. models from year 2000 suffer more as each coil fires both plugs on the same cylinder. 99 or older models you hardly notice even a completely dead coil.