I know I'm new on here, but I have never had a problem with my '96 F150 before now and I have over 100k on it. So here goes;

About a month ago I got a set of codes I cant remember which it was 4 codes all related to the operation of the O2 Sensor on the drivers side before the cat Bank 1 Sensor 1. The 2 standard codes I think P0131 and P0132 and the 2 that I have had come back now. I replaced that O2 sensor and the code went away immediatly without needing to be cleared. I just started the truck and gone. So its been a week or so since replacement and these 2 came back P1131 and P1132, indicating both lean and rich operation and the O2 not switching. So my question is where do I go next? I am probably going to clean the MAF just to be sure, but could it be a fuel pressure regulator on that rail causing the problem?

Thanks for the help.

 

P0131, P1131, and P1132 all refer to the PASSENGER side upstream O2 sensor. I don't see a P0132 code anywhere.

Sounds like you replaced the wrong sensor. Jusr swap the upstream sensors if you don't wish to purchase a new one.

Steve

 

I'm just a shade tree mechanic, but from what I remember Bank 1 or Bank A as Ford refers to it means the drivers side and Sensor 1 is the Upstream sensor. Another way to look at it is Bank A refers to the side of the engine block that Cylinder 1 is on and from what I can remember on this engine is that it is on the drivers side, but I don't have a firing order diagram infront of me... can anyone shed some light on if cylinder 1 is on the drivers or passengers side?

*edit*

Also, I am working on the V6 in case it matters.

 

I got an engine diagram for this truck and found out that infact Ford did put bank 1 on the passenger side on this truck, which is backwards of most vehicles. I will switch the sensors over and see if that fixes the problem. Thanks for the help projectSHO89.