Hi when cold my g60 runs rough not on all cylinders then when driven in the first minute or so can cut out if accelerated too hard. It makes a slight shudder sound before the engine dies! The engine has a rally cam stage 4 charger 68mm pulley and tsr head but used to run fine. I have ordered some new plugs bosch w6 dpo. If anyone can shed some light on my problem it would be much appreciated.