Approaching 150k miles, replace front O2 sensors?

[tahoe7689]

I changed mine because I had a low voltage code, and after changing them I could tell a small difference in responsiveness, but if yours aren't throwing codes, I'd leave them alone

 

[ktmhans]

Between the two tanks running 93 non-ethanol gas after changing sensors I monitored the first tank at 13.6 MPG and the most recent tank at 14.55 MPG. I don't know if this was the only fix to my old 10-11 mpg but it has def gone back to normal range. I still thinking of replacing the MAF due to random starts that instant cut-off. For the $60 and do it yourself change, I would say do it. It didn't hurt my pocket to spend the $

You say you dont know if this was your only fix to your old 10-11 mpg. Did you do anything else in between checking? Have u been running the same 93 octane fuel