'91Z TPI Auto.

I drove it today for the first time in a while and I put the gear selector from Park to Reverse and I was waiting for the jolt, saying it's in gear. Didn't do anything, so I gave it some gas and it finally went into gear. Same thing happened when I shifted into drive. Wasn't shifting without some hesitation either (had to get off the gas for a few seconds)

So what needs to be fixed here? Don't tell me slipping trans, is it the detent cable or something? And how do I go about adjusting it? The TV looked like it had too much slack, but I didn't think that would make the gear selector not select a gear for a few seconds.

Help!

The fluid is fine BTW.

 

"Don't tell me slipping trans"

Despite that antagonistic aproach, I'll try to help.

Once it went into gear did it then work normally or did it continue to do this?