How to repair P0171 on a Chevy cobalt

Question

Engine runs smooth but also throw code C0561

Answer 1

C0561 System disabled , (traction control)

P0171 fuel trim lean Bank 1

When you set a C0561 and there is a "P" code preset, the traction control is disabled, the reason the vehicle is  not operating at manufacture specification .Also  when there is a Lean code (p0171 )  for this vehicle disregard any transmission condition such as harsh shifts, until the lean condition is resolved,