jim warman

It is rare for a lack of O2 switching to be a faulty sensor..... In 30 years
I have replaced less than a handful of sensors and usually for heater
malfunctions. I would suspect an engine related condition before I simply
replaced an O2 sensor on a whim.

HTH

csb

Thank you for that. I think i figured it out, it would appear that my
local lube place over filled my oil, I got my hands dirty and chaged it
myself then reset the comp, so far so good and no more frothy oil.

shoe salesman

Yes...but...192K miles on ANY O2 it will be worn out.
I don't let my own go more than about 60K. They wear out just like other
parts. I wouldn't replace the rear one(s) but the front...yep.

jim warman

Curious.... in all these years I have yet to replace more than a handful of
O2 sensors.... I had a 4.6 F150 last month... had a bad heater.... all the
other O2s looked good..... and only 400,000 and some kilometers on it.

Back when these things were in their infancy, many manufacturers suggested a
replacement interval for these sensors. Technology has come a long way and,
in all honesty, O2 sensor codes are, for the most part, symptoms of another
problem. I can't understand how some DIYers see the need replace more O2
sensors than techs in the field.

shoe salesman

They replace them because they think it will fix the car I guess. But don't
be fooled by a lack of codes, O2s can be "lazy" or worn, or covered in so
much mud and tar and such that it can't breath well. At least that's what
they taught me in grease monkey school You have never had a ford with a
sequential injection idle rough because of a lazy O2 on one side? I have. I
also like to check them with the scan tool to see if they don't hit damn
near 1 volt at WOT. I do agree they get changed for other reasons that they
never fix though. Like O2 codes from low fuel pressure.