2001 Escape Oxygen sensor help please
 

I have a 2001 Escape XLT. Its throwing a code for Bank 1 sensor 2. I also have been getting reduced gas mileage the last year or so, which makes me think I may want to change all the O2 sensors. I think there are 4 sensors on this vehicle, and I have found them being sold all 4 in a package (2 upstream and 2 downstream). Can someone tell me if both upstream sensors are interchangeable with each other?Does anyone have a diagram of where they all are and which one is which?

Post the actual fault codes if you don't know for certain what you are doing (which is evident).

Thanks for your reply. I have 2 codes:

P2270 O2 Sensor Signal Biased/Stuck Lean Bank 1 Sensor 2

and

P2271 O2 Sensor Signal Biased/Stuck Rich Bank 1 Sensor 2

I know this is on the downstream so its more about emissions than gas mileage. I have 140k miles and still on original sensors so I figure Id just change them all at once. I can visually see them if I look, Im just not sure exactly which one is which.

It's more likely that spark plugs may need to be changed instead of all 4 O2 sensors assuming you have a V6 (not specified) in regards to fuel economy. How old are the plugs?

Are you sure about those codes (and the model year)? Ford's service documentation shows those codes as first being used for the 2003 model year.