I am looking for the air injection pump or may be called leak detection pump. Is it behind the left rear wheel? The part I see there has filter wrote on it. It has several air hoses on it. The dealers have spun me around trying to get the check engine light off . po442 small leak. They have done the smoke test and the system doesnt leak. Please help.

 

Is this the same error that you get when the fuel fill cap is left off or loose?