Hi Aaron,

I think it would help if you invested or at least have access to a 4 gas analyser to do these sort of jobs. Would be interested to know what they are before and when vehicle runs rough. I am thinking along the lines of either an engine or ignition misfire. What plugs have been fitted and have you any means of seeing the spark at all four cylinders. If you have a timing gun, you could use this to detect a misfire by watching the flashes..

Regards

Pete M