I too am new to gen 3 hemis my problem may be coming from somethimg in these posts had to replace an engine in our 04 Durango non mds reman engine shows up and doesn't have mds plugs or solonoids so order up 4 plugs and put them in as I was told that is only difference between non mds ormds engines 5 months later hasn't made it out of my garage yet when you first start it it seems to idle decent but after about 30 seconds or so sounds like it has a couple weak cylinders and no power revs slow and sounds like a 4 or 6 cylinder shut it off let it set a couple minsutes start it and the same scenario replaced practically every sensor fuel pump plugs twice one coil pack acts like lifters pump up and let it drop cylinders would this act that way from putting just the mds plugs in instead of the dead solonoids