Misfire: '02 Taurus 3.0L Persistant CEL P0302
Title says it all. Idles rough, minor surging when cold. CEL after running ~half hour. CEL flashes when accelerating uphill @ freeway speed.
Changed fuel & air filters, tried injector cleaner & mid-grade gas for 3 tanks.
Replaced plugs, wires - No change = P0302
Replaced injectors - No Change = P0302
Swapped #2 & #5 plugs - No Change = P0302
Swapped #2 & #5 injectors - No Change = P0302
Swapped #1 & #1 wires - No Change = P0302
Replaced crank sensor - No Change = P0302
Guy @ AutoZone suggested that because the upper radiator hose was hard when engine is warm, air trapped in system and maybe marginal thermostat operation. Replaced thermostat/coolant. Ran 3-4 hours longer before CEL. (Still seems to have air in the system, but I have been unable to get it purged.) This seems promising, but CEL/P0302 persists.
I'm stumped! Consistently gets a P0302 code, sometimes P0316 code. It never shows a misfire on any other cylinder. Coil pack? Would that be consistent with the cold idle problem?