Picked up another z28 with auto this time need help!!

[fasta**z28]

hey everyone !! i recently picked up a 96 z28 auto with 90k , well it wont shift out of 2nd so no drive and overdrive i found a broken tps , replaced it no change. i dropped the tranny pan today emptied all fluid from pan and lines going to cooler and changed filter , gasket and both a and b shift solenoids . Now when driving only at wot it will shift from 2nd to drive somtimes? so what im asking is all of you with 4l60e can u give me any ideas on whats going on ? asr switch isnt working also? please ant input would be great !! thanks much appretiated.
joe