Occasionally at startup the engine will run rough and lope like it has a full race cam. Then unless I rev up the engine it dies. Also when in first gear it lopes and jerks when going about 10 mies per hour.

engine runs well at idle, then tends to begin missing , then serious lurching. Won't run warm at idle unless holding at 3000rpm+. Diagnostics says ignition misfire,,,,, anything from plugs, wires, to distributor, coil, etc? Can anyone narrow it down? Parts are costly!