I have been suspect of that cable so I replaced it. It made no difference. I think a key to my problem is that the sporty misses big time when cold - complete with flashing CEL but when it gets warmed up it runs pretty well. Could coils act that way? They seem like the next logical thing to check.

From the KIA web site here are the things to check for a P0302.

Any thoughts on which might be improved by a warmed up engine?

Vacuum leak in air intake system
À CKPS circuit malfunction
À Ignition circuit malfunction
À Faulty ignition coil or plug wire (I've replaced all but the coils)
À Spark plug malfunction (spark plugs replaced)
À Low compression due to blown head gasket, leaking valve or piston ring
À Low/high fuel pressure due to faulty pressure regulator, restricted fuel lines, plugged fuel filter or faulty fuel pump (fuel filter replaced)
À Fuel injector circuit malfunction
À Faulty fuel injector

Any other ideas or suggestions?