P2098 - help reading O2 graph

[Pascal32]

Father in law had a check engine light show on the drive over to our place. Pulled the codes- P2098 Downstream Fuel Trim system 2 lean. Condition seems to be intermittent- light went out a few restarts later.

Need some help- using obdII (don’t have a scope) I graphed the downstream O2 sensors bank 1 and 2 against each other and bank 2 looked to be hanging around .75-.8v so I swapped the two downstream sensors to see if the sensor was off or it’s really a bank 2 issue, no change in results.

Next graphed of bank 1 and then 2 up and downstream along with speed and throttle.

Should the voltage d the downstream be hanging around .75? I was expecting closer to .5, wondering if the truck is running rich

also the bank 2 shows more variation on the downstream than bank 1. Seems to be more noticeable under throttle

Appreciate the help!

 

[Tach_tech]

What year is your truck? There was a flash update to address false dtcs and P2098 was one of them. Have you graphed the upstream sensors? They can cause that etc as well. Any exhaust leaks.

 

[Pascal32]

What year is your truck? There was a flash update to address false dtcs and P2098 was one of them. Have you graphed the upstream sensors? They can cause that etc as well. Any exhaust leaks.

That would be helpful! He has a 2011 1500 SLT with the 4.7.

Attached is the up and downstream on bank 1 and bank 2 (see legend for which is which)

thabks!

 

[Tach_tech]

Ok, the flash update only applied to 5.7 trucks. If there’s no exhaust leaks I would try swapping the upstream sensors.