The codes you are getting I believe relate to a misfire in cylinders 5 and 6. It could be coil related or sensor related. Next time it stalls check for spark on 5 and 6. I don't have much hands on with the KIA. Looking at the wiring diagram it appears to show an ignition coil assembly with 3 coils inside. Each coil fires 2 cylinders but the cylinder numbers are not shown. Three wires connect the Engine control module to the coils; white, yellow and black. Also a pink wire from a fuse to a condenser inside the coil assembly.05 Sportage stalls intermittantly. Showing P0305 and 306 codes. Could this be a coil problem? If so do I have single coils or a coil pack. It is a 2.7 engine.