My CEL has come on scanner says P1131
O2- Bank 1 sensor 1 heard it might not be the sensor and no real answer

 

In most cases it's getting a false reading. One thing that happens often is th MAF gets contaminated. More so if there's a oil coated air filter like a K&N. It can also with regular filters. Try cleaning the MAF with a MAF cleaner. It can also with a vacuum leak after the MAF. PCV system for instance.

 

Ok, i cleaned the MAF and its not giving any codes for the MAF just the o2. Where do the vaccum leaks normally occur i replaced a few lines recently

 

Did the start before changing the lines? There's no specific place for a leak. Chek all the lines to the intake. The PCV valve can cause problems too. Make sure the hose to the valve bdy is tight and not leaking.

 

Do you have an exhaust leak at all on that side? I just threw two codes on my truck, one being the o2 - fixed the exhaust leak, and that fixed the codes.

 

i Have replaced the driver side top O2 sensor and replaced vaccuum lines and alsocleaned the MAF there is no exhaust leak that i am aware of. Im running out of ideas.

 

Hello everone! I am new to post but not new to the forum, thanks for all the good info you all provide.

Original post:
"My CEL has come on scanner says P1131
O2- Bank 1 sensor 1 heard it might not be the sensor and no real answer "


Bank 1 is the passenger side. Bank one refers to the side of the engine with the #1 cylinder. Swap the sensor with the passenger side, reset the computer and see what happends.

 

Ya it was the passenger side, but all along i had been told it was the driver side, so now 2 new front O2 sensors

 

How big of a job is it to change the O2 sensors on a 98 F150 with a 4.6L?