a while back my car started missing and popping a little bit, it wouldn't do it much then it would run pretty good so the other day i changed the plugs and they were solid white its running lean as hell what could be the problem i was wondering if it could be the o2 sensors
O2 sensors are possible but I would start by looking for a vacuum leak, cleaning the mass air flow sensor(especially if you have a K&N filter), checking fuel pressure, and the EGR valve. If these all check o.k. you may have an O2 problem.