Hi.
I have a 97 taurus which is 140k on it. It shows an error code p1131. What I found is "Lack of HO2S switch - sensor indicates lean". What is that mean? Do I have to replace the O2 sensor to fix the problem? Or anything wrong? Would you explain to me?

Thanks.

 

It's possible that the O2 sensor is bad being is a 97with140K miles on it. The P1131 code is "Lack of Upstream Heated Oxygen Sensor Switch - Sensor Indicates Lean - Bank No. 1". Double check the connector for clean contactsince bank #1 gets all the salt, slush and road crud.

 

I will check it up first.
Thanks.