Automatic Transmission Control Module problems of the 2002 Kia Motor Spectra

Car was 4 weeks old when engine light came on for the first time - called dealer said it was due to gas tank cap. Made appt w/dealer - next day engine light off - following week 6/18/02 engine light came on again it went off before dealer appt. Engine light goes off and on randomly. Finally engine light remains on at all times. On July 10 take to dealer keep car over night replaced transmission control module. Next day July 11 having traveled 125 miles engine light comes on - at highway speeds gears did not shift properly at times unable to acclerate past 50 mph - engine revved locked in wrong gears for speed traveled - had to pull over to shoulder several times to try and get gears working right. With exception of a few hours engine light remained on . So far dealer finds nothing wrong as engine light want off mere minutes before my scheduled appointment. Also trunk release on hatchback only works 1/3 of the time the rest of the time it opens half way and you must use key.