Will a fuel filter make my CEL come on?

What is your question?

My CEL came on. I took it to auto zone, they told me that it was my fuel filter/pump. I then took it to a shop and they said a fuel filter will not cause your CEL to come on. They hooked their scanner up to my truck, then told me it was my rotar cap for spark plugs (I think) and my o2 sensor. I've gotten the rotar cap replaced since they said I can go longer without getting the o2 sensor done. My CEL went off after replacing the rotar cap bit came back on 2 days later. Do I really need to replace the fuel filter or the o2 sensor? Oh by the way, the truck hesitates like it's going to cut off while I'm stopped at a stop sign or traffic light......any advice?? Please help lol