I have a spit and sputter problem with my 88 Cherokee I changed timing chain, cap and rotter, pugs checked one but not all and had a clog in muffler that i just fixed. I can drive for a lil while few miles or so then it start sputtering and has a back fire so thats what made me do chain. if iI leave it sit for a lil bit it will start up and run fine for a lil and then start sputtering again. when I pulled cap off of distributor the cap screws broke so I pulled my distributor out my old motor and put it in. Looking at the one came out and had really bad weir marks on it maybe 1/6 of a in. or so on the teeth. Was wondering if u could give me any advice on it or if u have any idea what could cause it.