Hello all;

I read somewhere that our 02 sensors can slowly go bad and have an effect on gas mileage.

My question is, IS THIS TRUE?

If I were to replace the 02 sensors on my 02 5.4 (70k) would i see an improvement in my mileage (14-15 now)? Providing of course I drive in a reasonable manner. As you will notice, I do ALOT of driving and any increase in mileage is welcome.

Thank you in advance.

 

they are a maint. thing alot of people just say replace them when they break, but they slowly wear and effect the time they read. if your getting your 14-15 mpg i would say they are going to get you anything more... their fine. i was getting around 10mpg replaced 02's, new tps, cleaned iac and tb and now im getting about 14

 

Saint

My sensors slowly started to effect my mileage also, I had dropped from my normal 17-18 mpg to like 14 mpg. I finally thru a code for the upstream sensor. I replaced both and reset the computer. My last 2 tanks I have gotten 19-20 mpg.
I have the 5.4 with 120K miles.

Sled...

 

Has your mileage gone down from when you first got it?

If your MPG is the same as always, its not going to suddenly get you better MPG.

 

At one tiime I used to average 17-18 mpg.

an extra 2-3 mpg would allow me to go one more day without filling up.

While the magnaflow was going on today, I looked for the forward two o2 sensors. the passenger side looks like it is going to be a b*tch to change. Anyone have any suggestions on the removal?

ps. the magnaflow is far quieter than the flowmaster.....now no one will know when I sneak out of church or come home late!

Thanks guys for your input.

 

The first time I did the pass. side I took out the fender well liner. This last time a few months ago I left it in. I used a wrench instead of the socket this time, and it seemed a lot easier. Cut the wire on the one coming out, and it cuts down on the hassle a bit.,,,,98


I always hear they should be replaced every 25k for best mileage. Of course I don't do it that often.

 

Here's a good thread with some tips:

https://www.f150online.com/forums/sh...ghlight=sensor