O2 sims

[Hector]

> The info I've heard from a *Ford* tech friend is that the rear,
post-cat sensors do not switch,
> but so fluctuate a bit.  Supposedly the training he had from *Ford*
told him that the ECM would
> only look to see that it didn't switch...
>
> I have no clue, just spreading rumors.

Well, rumors that aren't that far off base. They are expected to move
but not with the front O2's. They aren't suppose to cross over but
will do so when you give it hard throttle movements and such. They
hover around <300mv otherwise. The thing to realize is that the ecm
(pcm,vcm,whatever) is not always checking to throw a code but it is
always monitoring it for tuning. O2 checks are run at certain times
under certain conditions, just like misfire checks, purge checks,
etc... OBDII isn't the easiest in the world as far as getting familiar
with it. I just took a 16 hour course for my continuing education as a
mechanic (not an auto technician, I hate that phrase) so I could keep
my license to practice my career (another point of displeasure) and it
was on OBDII. Let's just say that there are a lot of checks for the
O2's.

Hector
http://soflaspeed.freeservers.com



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