Throttle issue

Alright I’ve never had an issue get this bad so I’ve finally come to the forums. So basically I have a 2001 is300 with about 225k. It has an exhaust leak and needs a tune up but it drove pretty fine for a second until this one day I was doing a little bit more driving than usual and I randomly got a check engine light. It was for tps I think and cyl 1 mis x2 and a random misfire code. it also suddenly started revving high in park and at idle. I also had to press the pedal all the way to get 30% power. then concluded it was tps so I changed it and it only stopped the problem and turned off the check engine light and stopped the problem for like half a day. Than it came back on with the same issue. Then I bought a whole throttle body after concluding it was the APPS. Now the problem is worse, I’m assuming maybe this tb was just defective

any suggestions or advice