car acceleration is very sluggish

What is your question?

my daughters car has check engine light and traction control keeps turning off, and display says engine power reduced. ive had codes ran and say catalyst converter. so i pulled it off and checked and cleaned it. even put it back on and left rest of exhaust off and it seemed to be fine but she says it only gets sluggish acceleration when it cold, any ideas?

What makes this problem better or worse?

seems to do it when cold

How long has your 2009 Pontiac G6 had this problem?

she said its been doing it for several weeks