I have an 87 monte ss with a 2004r transmission. I pulled the computer, put a shift kit in it and adjusted the tv cable in a couple of positions and I'm having problems with it. First thing is that when I'm driving it shifts into 2nd ok, but I have to get the rpms up really high to get to third and overdrive. second is that while I'm driving I take my foot off the gas and the rpm's drop to idle and i have to get it back up to the same rpms to move again, and third is that it will start off in 2nd gear when I stop. I can put in neutral and back in gear and it goes back in 1st.

Need help

This is a good article that goes with the 2004r TV cable adjustment.

https://www.cpttransmission.com/tech_tvcable.htm