Ok. I'm having basically the same problem but by sensors are stuck in the low voltage range. And my odb2 reader never shows any change in the voltages. I ordered some new sensors to see if that would fix my issue. should get them at the end of the week.

 

I've never changed them out on one of these but if you're not driving it every day I'd soak it your favorite rust penetrate

 

I already did that, and removed them. It's not my daily driver, so no hurry here.

Never did get any Engine light or codes, but noticed the low O2 voltage and terrible gas milage.

 

Right on.

 

so, on a healthy Discovery 4.0 engine what voltages should we be seeing? and should it be consistent on either side or will driver and passenger side look different?

 

Don't know what the optimal range is but look at what binvanna posted (#7).

 

Not to thread Jack but what should the battery volts be at? I don't recall them changing but today I have movement between 13.9 and 15.2 while driving

 

Mine are hanging out in the mid 14's. Your numbers seem fine to me.

 

Alright, thanks. Then I wonder if it's something else that is causing my dash lights to pulse...

 

15.2 too high and normally indication of alt volt reg is bad. Likely causing the pulsing and will fry your battery due to over charging, in mean time check battery may be doomed unless fluid is added on regular basis until alt fixed..
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