Transmission only shifts at high RPM's

I got busy yesterday. And figured I have time before bears game today. So I have new battery in both testers. And i'm getting 0.64 steady with throttle closed. And when I open throttle it goes down to around 0.50 then comes back to 0.64 and then stays there. So I guess the TPS is bad. It all began after I put new intake gasket and cover. When I first started it the idle was really high at 3,000 RPM's. So I went ahead and changed the MAP sensor that did not work. So I changed the TPS that did not work. So I changed the temperature sensor that did not work. So I changed the idle air control or idle control and that worked. The idle came down. But then when I drove the car the RPM's were really high when shifting which is what we're discussing now. So I bought a second TPS. That's the one we're testing now. And clearly I got two bad TPS. I'm going to buy another one and try it. If it ends up messed up something is causing that to happen.

Plus I really didn't want to tell you because it's one of those mistakes you look around hoping no one seen you. Because you know better that to do it and not notice sooner. But here goes. The whole time I was testing the Idle Air control. Because it was the last thing I changed. And that's why both my 2000 and 2004 have 4 wires instead of 3. So stupid it's funny. Sorry. But the message before this is testing the TPS.

Pluss I really didn't want to tell you because its one of those mistakes you look around hoping no one seen you. Because you know better that to do it and not notice sooner. But here goes. The whole time I was testing the idle Air control. Because it was the last thing I changed. And thats why both my 2000 and 2004 have 4 wires instead of 3. So stupid its funny. Sorry. But the message before this is testing the TPS.

Okay, so all this time I was testing the wrong thing. Because my idle air control brought my idle down for some reason I kept thinking that was the throttle position sensor. And I know the difference I've changed them in many cars before. But thanks to you I finally stopped and looked at what I was doing in realized I was testing and changing the wrong thing. I put new TPS in and everything is great. Thank you for your help. That was all my bad I can't believe I really did that but I did.

Question: I am replacing the factory mufflers with glass packs on my 2000 Monte Carlo SS. 3.8 V6. And I don't know if I should remove the catalytic converter or leave it in for the best sound quality without sounding like I'm trying too hard. And no I don't have to take emissions.