O2 sensor voltages bad MGP

I have a 2002 with 2.7l. I was wondering what is a normal voltage range for O2 sensors? My MPG is 9 MPG and has never been this low, 140 miles per tank. The worst I have ever had before was 16MPG in winter. I hooked up a blue driver obd ll and the readings on bank 1 sensor 1 is between 3.212 - 3.310 v. Bank 1 sensor 2 is .060 and .840 v. Brakes are not dragging and wheel bearing have no play spin freely.

 

.01 - .98 according to Google

 

Does anyone know what would cause the voltage to be above that range?

 

Your B1S1 is a wideband Air/Fuel sensor. Works on Milliamps. The number given earlier was for O2 sensor.

 

Oh mannnnnnnnnnnn

 

Is it normal for downstream o2 to flux between .6-.8v at idle? .6-.8v at idle?

 

I have noticed at idle or driving that my coolant temp reading, RPM and short term/long term fuel trims drop momentarily. I know that is not normal. coolant temp dropped to -40 deg. fuel trims went down to -100. Rpms went down to zero, but the engine never faltered nor stalled.

 

this one was while I was driving 60 MPH

 

Probably a glitch in the communication between the scan tool and the truck.
Normal fuel trim is +/- 10% total (long term+short term) fuel trim.
Downstream sensor is there to monitor the catalytic converter, it has little to no input on fuel control. It should stay between 0.6-0.8v with the truck warmed up if the converter is working properly.
Do you have any lack of power, hesitation, CEL, or notice any difference in how the truck runs and drives other than fuel economy?

 

no just economy, but shouldn't the o2 be rising above .5v and below consistently at idle? I drove around in my van with non of these drops in readings.

 

Not the downstream it should remain steady at a slightly rich voltage 0.6-0.8 if the converter is functioning, that's how the PCM monitors converter function, if it sees the downstream switching rich/lean too much you will get a p0420 (catalyst efficiency low) code.
The upstream should switch rich/lean constantly except at or near WOT where it should stay rich.

 

Ialso have seen the rpm reading spike. I didn’t rev it up over 7000 rpm.