Hi I have a 2004 FX4 with a 5.4 I cannot get it to pass inspection I had an O2 sensor code I erased it and now the computer will not reset. That was at the end of 2021 and its been the same story month after month the computer isn't ready. The truck has 227000 miles on it.

Thank you,
Jeff Newinski

 

Which of the items is not ready? The catalyst monitor? Evap monitor?
do you have any DTC stored?
We need more details to be able to offer helpful advice.

 

Hi as far as what's not ready all the o2 sensors it's been that way for over a year I even tried resetting the pcm and I also got a new battery. No stored codes. I am running out of options.

Thank you
Jeff

 

Here is the paperwork that states what's not working right.

Thank you,
Jeff

Sorry for the bad picture.

 

Ok makes more sense, but as to my other question, does your check engine light work and is it on?
are there any DTC stored?
I would think that if there is a problem with your 02 sensors that the PCM would have some codes stored which might help off further suggestions.

If you don't have a reader take it to a place like AutoZone and they will check it for free and print off the codes for you.
My gut would say perhaps you have a wiring issue or a blown fuse to the rear hego/ o2 circuits. but would think there should perhaps be DTC reflecting something nof the sort. There are fuses to check, wiring down by the cats that can get melted if they hang down and touch the exhaust, and there is a connector next to the PCM that can coil be loose or have some oxidation in the pins that should all be checked in my opinion.


My personal F150 has an occasional p0420 code for catalyst low efficiency, but if I reset it and drive about 10 miles I can usually get the readiness monitors to all set and get it to pass emissions before the light comes on again. My point being if things are working properly the readiness monitors don't take long to be set as good....

 

My light works all they keep saying at inspection is you have to drive it for them to reset well I've done that. I did have a trans code show up like a week ago but that's about it. I have a obd2 scanner and it says all monitors are not ready.

Thanks
Jeff

 

Here's a good previous post with lots of info:
https://www.f150forum.com/f4/failed-...482464/index3/

 

Remove and inspect fuse #33 in the fuse box inside. Confirm it's good with continuity tester.

unplug the 12 pin gray connector above the PCM. Inspect for corrosion. Reconnect tightly.

Inspect 02 sensor wiring below the truck next to the transmission.

 

OK thanks for the information.

Jeff