After giving my 94 1500 2wd suburban a badly needed tune-up in which I
replaced the alternator, battery, plugs, plug wires, Belt, Distributor,
Cap, rotor, and a new starter. She ran like a dream for 3-4 days when the
missing and backfire came back and started acting like nothing had been
done. I then tightened the throttle body plate and checked all the hoses
for obvious leaks and connections for the many sensors. Rechecked timimg,
checked fuel pressure and read 13lb as spec. Compression is 110-125 lbs
all around. All that seemed well. I replaced the plugs again with new AC
Delco and the rig ran like a champ again. It?s been one day since this
last work and the missing is coming back again fast. The missing is coming
under any type of load. I pulled the plugs again and they don?t look that
bad accept #5 is carboned-up.