Yup thats it, quite the PIA because the entire procedure must then be completed AGAIN. Probably why mine was hung up on that one for at least 1000 miles (I think the upstream O2s were lazy also... I replaced them, no codes, and soon thereafter was able to get inspected). At 155k on the originals, I figured their accuracy wasn't exactly the greatest.

 

Where'd you buy your O2s? Can you use the same sensors upstream and downstream? Mine are originals and I'm wondering if it's time to replace.

 

I’ll have to check my records, but more than likely Rock Auto. I try and buy everything I can local to support my community and those who live here, but some items require OEM stuff and not “auto parts store brand” stuff. I used Bosch’s IIRC...actually did the upstreams twice, first with Advance sensors and then again with MC or Bosch bc I wasn’t sold on them. They may have been fine but sometimes my vehicular OCD gets the better of me.

 

@dukedkt442 What's the best brand of O2 sensors, besides OEM Motorcraft? Denso, NTK, Bosch, ect?

 

i think it’s a crapshoot. I replaced the 2 upstreams on one of my cars with Bosches preventively at 100k because Bosch is the OE supplier, and those are now getting lazy and throwing codes 60k later, and I’ve heard of them failing in as little as 20k. When I computerized the ‘76 engine in my Olds I used a Denso and it’s been fine for 10k miles. I would say that an OEM or at least name brand is of great importance, at least that’s what I use when I’ve done them for other people, but don’t expect them to last as long as factory. I killed the downstreams in the first car I mentioned above by vibrating the pipe with an air chisel when replacing the downpipe gasket at 155k. I used either Bosch or Denso in my old MK3 Jetta at 100k and took that car up to almost 200k before I sold it without issue. I don’t really have much personal data to support any decision, O2 sensors are things I seldom do because I hate exhaust work.

I did learn early on with the F150 (and my Germans) to use OEM with vital sensors and hard parts like phasers, as I’d imagine slight changes in resistance in the sensor would alter the PCM’s interpretation of its readings, so that’s ultimately why I went with the MC sensors.

 

Over the last couple of days, I have drive the truck a bit. This afternoon, it had a hard slip/engage at around 50mph. No check engine light came on. If the ECM isn’t reset yet through the drive cycle, will it throw a warning light?

A previous problem that I thought was cured from servicing the transmission appears to have shown back up, except this time it is without the check engine light.

This is discouraging

 

If that event is the common 5.4 misfire, that would definitely prevent the truck from clearing the P1000. It would really help to see data logs for misfire counts, fuel trims, and to see what test module the truck is hanging up on.

 

Ok. It seems like my next step will be purchasing a scanner. I’ve seen some things regarding Torque Pro? Not familiar with this but will look into it

 

Have you changed the spark plugs? As @dukedkt442 said, if it is the common 5.4L misfire under light acceleration at 45-50, then that's an indication you need new spark plugs.

 

I did the plugs right around 110k. Just the plugs. The truck was driven steady and consistently with a lot of highway mile driving due to work up until about 187K. The truck was not driven nearly as much over the last 2 years, so perhaps that could be it. I will start throwing money at it in regards to plugs, maybe getting a scanner, and whatever else I can think of before pricey endeavors.