I have an intermittent miss in my 2005 LLY. It is worst at light acceleration or steady throttle. If I accelerate hard it runs as it should. The miss feels the same as a gasoline engine would with a bad plug wire or spark plug. I have changed fuel filters twice, many tanks of fuel from different stations, Diesel 911 in the red jug added, all with no change. No check engine light or DTC's. 105,000 miles, no change in driving conditions or habits. I would appreciate any help prior to going to a dealer and paying mega-bucks for poor results. Thamks.