I did a reasonably good site search and couldn't find the answers.

I'm about to embark on one of my favorite jobs on my '01 5.4 SCab 4x4, changing the spark plugs which will be the stock Motorcrafts.

As long as I am going to schedule the best part of a day to do this plug change out, I need an opinion on whether to change O2 sensors as well, and if so, which ones. Generally I see postings that only the fronts normally cause a problem. Is this the consensus - or do I just say the heck with it and let them go until I have a problem. I will be changing the fuel filter and "dusting" off the MAF as well - need to get as much gas mileage as possible and if a few bucks with these additional components has a reasonably short payback time, will include.
As far as the O2 sensors, which seem to perform the best. The local parts folks sell Standard/Blue Streak, Bosch or Denso - Motorcraft is a tough find.

Are there any other parts that I should consider - there are no fault codes (at least today) showing

Thanks
Dave

 

See my post about this in this thead https://www.ford-trucks.com/forums/5...fo-on-mpg.html
my comments about O2 sensors are at the end.

-Kerry

 

Kerry,
It sounds like with the gas mileage I am getting is about what you have reported in the thread . Based on that, I ain't gonna touch a thing with the exception of the plugs which I already have plus a new fuel filter and I don't have much in the way of mods.
My 28 foot travel trailer can pull it down to 10 - 11, depending on how fast I push it or whether there is a head wind, etc. An car trailer is ~13. And I mirror about everything else.

Thx,
Dave

 

I changed the O2 sensors on my truck and let me tell ya, the gas gauge DEFINATELY doesnt move as much as it used to. It seems to run better too.

I got mine here: http://www.autopartswarehouse.com

I also replaced a couple other sensors for cheap from there as well. The Oxygen sensor was a denso OEM style and it works fine. I only replaced the one before the catalyst however, as that is what contributes to your gas mileage anyway. The back one just checks to see if it is on and working.

 

www.rockauto.com

Check prices here too.


KO

 

And if you guys want Factory OEM check my site.

Ed

www.discountfordpartsaty2kford.com

 

[QUOTE=discountfordpart]And if you guys want Factory OEM check my site.

Ed

www.discountfordpartsaty2kford.com[/QUOTE]
Ed,
Thanks for the web site. OEM is nice for many items but very pricey in comparison to Denso and Standard for these sensors. I do plan on bookmarking the site as there are a lot of OEM parts I do prefer over aftermarket.
Dave

 

Dave, do a comparison on the next part your looking for and let me know where I'm at price wise.

Ed

 

My 2000 F150 with a 4.6L has about 120,000 miles and I have never replaced the O2 sensors. Would it be a good idea to replace them to get better millege or should I wait until the service engine light goes on for replacing them?
Thanks

 

Ed
I will do that - luckily, I don't seem to have many problems with my truck....yet.
Your site is well bookmarked

Now, my 5.0L crate motor in my '31 A may be a different story !!!
Dave

 

Apprently you don't have to wait... my mileage has never changed by keeping the original factory units - but, as you can see, others say different.

-Kerry

 

Is there a difference b/w the Bosch and Denso O2 sensors?

 

Which O2 sensors did you replace, upstream or down?

 

What are the symptoms of a bad O2 Sensor? I had my code re-read and left bank O2 Sensor came up. I have a slight miss, or sputter in the engine at various speeds. I don't lose speed when accelerating and have been told by several mechanics that it is not the fuel pump. I would just like to know the symptoms of bad sensors.

 

02 sensors have resistance readings they should be in the range of. By using an ohmmeter or multimeter, you can compare the readings of the two sensors at the connectors. I'd also bust the suspected bad one loose from the bung and look at it... clean it off with alcohol and see if that doesn't change the code, if you get a resistance that is pretty close to the good side. Sometimes a carbon deposit will end up on the sensors from an abnormally rich run and gunk it up a bit. A black soot is normal. A cleaning of both sides may help, as well.

-Kerry