i do take it to mechanic he take 700$ from me he change some parts and he said check engine light well go of. every time i drive the car it come back
after 2 month going and back to this mechanic he said he dont know why the light come back
i do smoke test they told me everything is fine no leak
i went to another mechanic he said o2 sensor is bad and fuel filter and the fuel injector. i pay him and he change it same thing same error
so i stuck with 2 errors p0410 p0440
and the last person who try it a friend of me he said the brain coast all this change it
You obviously have gone to the "wrong" mechanics.....the O2 sensor, fuel filter, and injector, have nothing to do with those two codes.....
Bite the bullet and go to a GM dealership....