Hi everybody. Im new to this site and im very impressed with it. The problem i have with my car, is that it was running lumpy, so i changed the lead's and plug's. No change. Then it wouldn't stay idle on turnover. Now it will not run at all, after it backfired. Im now being told it could be a lot of different thing's at great cost. Does anybody have any idea's what the solution could be. Many thank's.