censores

Hello, I am a new aki on this page I hope that I can help me, I thank you in advance for the problem that I have with my car a Ford Explorer Esport of 2001 is an oxygen sensor, but I have not been able to find what the sensor is the sensor that this is already badly changed two those who are before the Catalitical but still the problem is only in the morning hot the car and that fault is lost and more than everything in winter for the cold gets worse I hope you Pode me ajudar obrigado