yea,it puts out alot of white smoke till it quits missing and then it will turn to gray and black. im thinking its one or more injectors also. ive got a set 370s just havent got around to putting them in. kind of waiting to get enough green stuff together to get a dtt or ats trans rebuild,and another plate,191 dv,turbo,exhaust. put the banks kit in when i got this truck and before i learned a thing or two from this site. the banks kit helped but its overpriced,hoping trans holds out till spring,then the fun will begin.