2011 Chevy Malibu throttle body problem

I bought a 2011 Chevrolet Malibu 2.4. A month later
the reduce engine power and traction control came
on, I took it to auto zone and the codes came up
P1516 and P2101, well I changed my throttle body
today and when I turned the car on the rpms shot
up to 3 and when I put it in drive or reverse it goes
back down and accelerates on its own when I drive
it. Can’t figure out what’s the problem.