TCS light turns on and then acceleration is erratic

The traction control light simply means the ABS thinks that one tire is slipping more then the others so it normally will pulse the brakes to try and even them back out.

Here is a guide that will give a little more detail on this:

https://www.2carpros.com/articles/abs-warning-light-on-easy-repair-guide

https://www.2carpros.com/articles/abs-wheel-speed-sensor-test

I would suggest we start with checking for codes with a scan tool that can pick up ABS codes as you likely have some there.

https://www.youtube.com/watch?v=rTtAnsOlZU4

https://www.youtube.com/watch?v=jr_Iv8T_Phk

Please run through this material and let us know if you have codes and we can go from there. Thanks