07 cadillac cts 3.6v check engine light code p0021 Timing Over-Advanced or System Performance (Bank 2) hard starting, poor idle only symptoms. What can i do to fix it? just change the sensor or is there something else to do?" I have warranty on engine for 600 miles or 2 months

 

thanks for the help Oo but i found that the engine was replaced and the dealer never told me that. I going to try to return the car , the check engine light IS ON again and i take the car to the cadillac dealer and they told me i have multiple trouble codes ( 19 diferent codes ) B,C,P,U, .
well a lot of problem ... can I take legal action ?