layitlow04

i have a 1993 lexus es 300 that seems to be stuck in third gear and will occasionally shift into overdrive at 60mph@5,000rpm(sometimes) i just changed the fluid and the trans filter. the fluid was dark but by far not the worst iv'e seen. i have pulled the EFI fuses and disconnected the battery for lenth of time to reset the ECM. No Luck, I also used an expensive snap on scanner to scan the computer....no codes at all. it just produces a constant CEL blinking light which states no codes in the ECM. Engine runs fine. really sluggish on take off so i know its stuck in a high gear. Someone please help. How do i know if i have a bad/stuck solenoid??? any input would be greatly appreciated.