Just recently, my 91lx 5.0 stopped running all together. One day it died on the way home, got to a parts store had didiagnoses done, o2'S were bad, replaced them still ran with hesitation. Come to find out later plug wires were bad, fixed that too, EGR, TPS also. Now won't start and backfired on me. Any idea's before I go postal on my stang?