I long agreed to your mind - the oxygen sensors are always overlooked - when one plugs the OBD scanner and analyses the fuel trims - short term to long term - often one will give a clue to the front or lambda sensors which are crucial to maintaining the correct air to fuel ratio and that is where I am suspecting this on my 2013 Nissan Juke 1.6 and the tell tale sign is the abnormal topping up of fuel in less than one week or so - so precisely you are right there.
@@dnaauto Alright. I had my old lambda sensor checked out by mechanics and they said that there was some damage done of trying to remove it (previous owner). I had the brand new one and rear oxgyen sensor installed on it, and it is running better. Before this, my OBD scanner read that running from rich to lean failed. After the installation of new sensors, it said, "Passed". Another overlooked factor, like you said, is the air filter as well. Very easy D-I-Y. The mechanics struggled to remove the front sensor, so they called in the thread repair guy who had specialized tools to remove it because it was sitting on the line pipe next to the turbo assembly. New thread bolts were installed and everything was running better. No more of P0420 errors.
U just omitted the very very very significant thing that may cause the car to consume a lot of gas,that one my brother is a dead turbo, Talking from experience.
