I have an 89 firebird, i had a 700r4 tranny in there, the 3rd and 4th gears went out after messing with the detent cable, got a
45 dollar 700, got it in and guess what same thing only 1st and 2nd gear, i used the same torque converter had a higher stall cause i plan to cam it up soon, could it be the torque converter or is this tranny f#$#ed too,

 

45 dollars for a trans should of been your first clue something was wrong with it. you now have 2 transmissions that don't work and even if the TC is good i'd consider swaping in another one since all the trash from the trans ran in it too

 

The question i was really asking was can the torque converter be the reason that the tranny is not shifting in 3rd or 4th, i used the same one from the old tranny, and was wondering if it was that, or can it be possible for the detent cable to be bad or stretched or something/.

 

No!