2001 extended cab slt 4x4 4.7l automaticP0201 cyl 1 open circuit p0171 bank one lean Intermittent issue only when truck is on the highway. Running between 1950 - 2100 rpms Moved cyl 1 injector to cyl 5 to verify its not the injector. Changed cyl 1 pigtail verified pulse with noid light
data from code trip:
Rpm 2055 ,
69 mph ,
192' iac ,
11 in/hg on the map
38% load on tps
O2 voltage pulsing between .100-.600v ,
Stft b1 38.1% ,
Ltft b1 33.8% ,
Stft b2 17.9% ,
Ltft b2 1.0% .

Tps 8 months old
All injectors new
All o2 new
Iac motor 8 months old

Im unsure as to the culprit now. There is no idle issues and in town ( non highway ) there are absolutely 0 issues. 295 miles in town no issues. 18 miles on highway cel lights up. Fuel circuit goes into open loop. Pull over cut truck off crank it back up and everything is back 100% normal. Back on the highway and repeat.

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What brand O2 sensors? How is your fuel pressure? The fuel trims seem excessively high to me......

 

The O2 sensors are NKT from all the research that I could do that is the factory brand I've already dealt with the whole it does not like Bosch and other brands this is my third Dakota. When i bought the truck and had a bad fuel pressure regulator and a weak pump so I replaced the entire unit and all of the injectors are nos Mopar.

The fuel trim is because it's going into default open loop and based on a live data it's doing it only on the highway and only when it goes into the kick down passing gear so I'm beginning to think it may be something transmission related as stupid as that sounds

 

So what i'm seeing is that the O2 sensors are saying it's lean and thus throwing 30% or more fuel at the table to try and get back to stoich. If your code reader is showing it's going open loop, then that's a whole other problem.

I'm not sure on the 4.7 trucks, but on the pushrod trucks, the transmissions solenoid pack share a ground with the oxygen sensors.

Part of me wonders if the trans is backfeeding through ground and upsetting the O2, which reports lean, the PCM richens to compensate, then the PCM faults on the injector driver.

 

This makes so much sense for the issue on the whole.

Update of po201 - tps was new but loosing signal , replaced and po201 is gone


​​​​​I pulled the PCM to send it back where I had it reflashed for them to verify that everything and it is good once it comes back I will see if that solves the problem and then I will go to chasing wires off of the shift solenoid. I never would have thought to check that because it gives no shifting issues

 

Update:

Pcm had an intermittent fuel injector driver failure. Waiting on pcm to be returned now to see if problem is solved

 

10/22/23 update

Pcm is back and installed.
P0171 still persistent
P0201 came back

Fuel trim issues still persistent

And new codes on snap on scanner are as follows
Transmission code 0400 description is check service manual and i cant find anything on that beyond it being egr related and the 01 4.7 doesnt have an egr
Transfer case code : "AF" again cant find any literature on this.

And an evap code for a shortened circuit in the heater system.