2016 ford f150 front o2s

2016 ford f150 3.5l non turbo has a noticeable misfire under load. Codes p0306 and p0300. Misfire counters at idle showed low numbers but thru out all cylinders all under 10 in a cycle. Anyways I went searching for my o2 sensors to make sure they were functioning. I found the downstream and they both read .7v at idle but were switching, they seemed to stay around .7v and went rich on wot test drive. My biggest issue I couldn't find a pid for upstream 02 sensor voltage or mV. I found uA which was reading around 80 at idle which converts to .00008 of a volt. This signal doesnt switch and go lower at wot so surely this isnt the rich/lean I'm looking for. I also found "impedance expressed as a V" pid which was a steady .09 and never moved for both banks. I'm not sure how impedance correlates with an o2 and I'm not excatly sure what it is to be honest but it's not the signal I'm looking for either. I also found a pid that said active sensor is not open circuit. When the truck was first started it would go from active to inactive back and forth once warm it would say inactive, I'm thinking it has something to do with closed loop operation. I'm confused as to what I'm looking at and where to find what I need. Please help! Pictures down below of dome scanner snapshot.









Side note: customer wanted new plugs since they hadn't done them since they bought the truck and they were way over needed. I'm almost 99% positive that was the issue the whole time and that I have fixed the truck. However I want to understand what I'm missing and why I cant find upstream 02 sensor values.

It’s a wide band air fuel ratio. The current measurement in the first pic ya posted is always supposed to be close to 0 milliamps

As long as you put OE plugs in, I'm sure you fixed the misfire. Weak factory ignition system, IMO.

As for the upstream air/fuel ratio sensors, here's my take. The 'impedence expressed as a voltage' PID is smoke and mirrors, and make it even more difficult to understand what's going on. The PIDs you care about are the sensor current in mA (as you found) and Equivalence Ratio Actual and Desired.

Off the top of my head, those Ford sensors will go to around -1 mA at WOT fuel enrichment and +2 mA during fuel cut decel. The direction of current flow is key - positive is lean, negative is rich. All others PIDs hold little value for me unless I'm trying to diagnose a sensor issue.

The Equivalence Ratio will tell you what the actual mixture is, and what the PCM is asking for at any given time.

For more info on air/fuel sensors, check out this thread:

www.scannerdanner.com/forum/diagnostic-t...-testing-thread.html

The values I was reading were in microamps. 80 micro amps is .08 miliamps. So is that number a good number to go off of? What's the range for these numbers as in -.1 to +.1 ma? Would I look at this signal the same as I would my upstream o2s? I had a feeling these were wideband sensor as I knew it was becoming a popular thing but I had no clue what it looked like and identifix is just calling them o2s. Ahhhhhh I was hoping their was a thread or video on this thank you!

1000 micro amps to 1 mA, so the numbers you saw are just fine. Unless there's a severe mixture issue or a sensor failure, the sensor will spend most of its time within 1 mA of zero.

You can look at the sensor signal for information about what the mixture is doing under various loads. Paul's WOT test for restricted exhaust or fuel delivery still applies to these sensors, with some adjustments for sensor design. Instead of looking for the O2 to go above 800 mV at WOT, this air/fuel sensor will go closer to 2 mA.

IDFix isn't wrong? They're still O2's, technically. :silly: I believe the Ford designation is UEGO. If you want to know way more than you ever wanted to about these sensors, check out the Ford OBD Theory and Operation for 2016:

www.motorcraftservice.com/freeresources/obd

Awesome thank you for the numbers. I will definitely be doing some more research on these sensors. As for now tho I've got the truck back with the same issue as before and I've got to make some headway lol

Check mode 6 this time betting its a coil breaking down

I agree, TID $83 in Mode $06 will tell you if the miss is truly on #6 or not.

You can also run the automated injector balance and relative compression to make sure you're chasing an ignition issue.

How do I get to mode 6? I cant find it I have a snap on verus and a autel at my disposal. Only thing I'm seeing is misfire data and it doesnt have much to go off of

I found out but didnt see a tid $83. However all cylinders passed and read a value of 0.

Have a P030X? Or P0316?

It previously had a p0306 and p0300 but I think that was taken care of by the plugs.