97 Yukon Idling rough and trouble reving

[SunlitComet]

the low voltage mean the sensor maybe dead as far as putting readings out. if you have done both fronts then do both rear to. Although the rears primary role is monitoring the converters they also play a small role in fuel trim as well.

 

[miskis]

the low voltage mean the sensor maybe dead as far as putting readings out. if you have done both fronts then do both rear to. Although the rears primary role is monitoring the converters they also play a small role in fuel trim as well.

Thanks, I was planning on testing to see if there is power going to the plugs and check to see if its the wires, and if the plugs got power then I'll end up replacing the back 2 as well.

Thanks for the help guys.