O2 sensor replacement, just how much of a difference does it make??

[pfran42]

Put a diesel in it. That will take care of all your issues with MPG's.


On the way to URE (318miles) I was cruising at 75-90mph and used 3/4's tank. On the way back I did the same and similar results. I hit Atlanta traffic and I barreled through the rest of the tank.

Re-read my comment, I screwed it up but then corrected myself. Seriously Nick. Do it and see what numbers you get. Maybe I have over-tightened wheel bearings, excess drag in my re-built diffs or fuel leak or something.

 

[MEMCruiser]

I had CEL on for years. Had 2 02 sensor codes and some bank codes. I started running NON-ethanol gas and after 5 full tanks the CEL light went off and no codes.

 

[Toy Fan]

I am not sure why the O2 sensors make a difference but I noticed a difference in mileage. I do keep fairly close tabs on my milage, especially when I take a trip. I had the DT headers installed and noticed an increase in milage right away even with CEL due to O2 sensor. That light wasn't on before the swap but I guess at 180k the removal and reinstall was too much for the original O2 sensor. I replaced the one bad sensor and saw another MPG. I just got 17 on a couple hour road trip this weekend and never saw 15 before the headers. I am still running all stock configuration except for the headers. I have heard of people getting sidnificant gains in mileage by running all synthetic fluids. I wonder if the guys getting better mileage are running synthetics in axles, trans, and transfer case.

 

[Nottajeep]

I noticed the protective tubing on the replacement O2 cable was black and the factory original O2 tubing was grey (bank 1 sensors). However, my ride is a 99 and not sure when denso changed the tubing color, but this might help if you are trying to determine original factory O2 components.

 

[natharmstrong88]

Before the O2 throws a code it will mess with fuel trim to the point that it impacts MPG. We've seen a number of users report similar results. 90-120k seems to be when the original O2's tip over.

I have just ticked over 250,000km (metric over here) and I would bet my bottom dollar that mine are still the originals. So perhaps I could benefit off changing them. I am running all standard ehxaust, with the removal of the rear resonator.

I know this fuel consumption topic is way overdone, but for the sake of a bit more info, I'l price two new sensors and if I decide they're worthwhile, I'l post up the details.

Right now I average (and this is the metric calculation, just to make you do the maths) 22.5L/100km around town, and an average of 15.5L/100km on the highway, sitting on 100 - 110km/h. or 60 - 66 mph. Running 35's with standard diff ratios.