I have a 1997 f150 with the 5.4l v8. It has approx 135000 miles on it. Ive had the truck for almost 4 years now and I love it. I put in a edge evolution in dash programmer, a k&n cai, and also true dual glass packs on the truck since I have had it. It recently has been throwing me some dtc codes such as p1000 and p1131. There was also one I can't remember but I was able to trace it back to my MAFS. I replaced my MAFS and all the codes went away. Now the p1131 is back. I believe it is my o2 sensors that is causing problems. I would just like to get some more info if anyone can tell me anything.

Thanks,
Sam

 

That's a lean code - the O2 sensor MIGHT be bad, but you could also have a vacuum leak or something else causing bank 1 to run lean. That's the front sensor on the passenger side. The P1000 simply means that all sensors have not yet passed a readiness test, this will set every time you disconnect the battery or clear codes.

 

That was exactly what it was. I took it to my local ford dealership and they said what you just told me. it was bank one sensor one. They gave me a deal and replaced it for me and my truck is running a lot better and i dont have any more codes showing!