P1151 Code for a 2000 Taurus

I have pulled the codes and I got a 1 of 1 - P1151 Lack of H02S21 Switches - Sensor Indicates Lean - Can someone please tell me what this is and how to fix the problem. With the price of gas now-a-days I can not afford to have my car running this way. Thanks for the assistance

P1151 is lack of HO2S-21 switches - sensor indicates lean. This is the bank 2 (drivers side) Oxygen sensor, where the sensor is not switching from rich to lean like it should. Now before you go out and buy a new O2 sensor, make sure there arn't other things that could be causing this to occure. A lean condition in bank2 can be caused by things like a vacuum leak from the intake manifold or some other unmetered air leak. Make sure you check this out first. However, if your car has over 100k on it, it is probably just the O2 sensor. They really arn't designed to last much longer.

Thanks for the reply - I hate to sound uneducated about these things - However - Where are the 02 sensors located, and what does it take to replace them - Do I need any special tools to install and or remove them? - Any idea what they run, cost wise? And do I have to go threw the dealer to pick them up? Sorry for so many questions - I do appreciate any assistance I can get - Thanks again

There located before the catalic converter.

---

They look like spark plugs and you will need a special socket to take them out or sometimes a wrench will do.

---

They cost about $60.00 each.

Thanks again - this has been very helpful -