Re: Oxygen Sensors when to change??

"Bill Putney" <bptn@[EMAIL PROTECTED]
> wrote in message
news:5uauh3F1h7kdhU2@[EMAIL PROTECTED]
> maxpower wrote:
>
> > Not true. The first purpose of the downstream 02 sensor is to  measure
cat
> > efficiency. The second function  is downstream fuel control. This
function
> > adjusts the upstream 02  goal  voltage within the range of operation
of
the
> > upstream sensor. The upstream goal voltage is used to ensure long cat
life
> > by allowing the pcm to control the amount of air and fuel that is
supplied
> > to the cat. If the downstream 02 sensor switch point is at a  low
voltage
> > the Pcm will adjust the upstream 02 goal voltage to reduce  high 02
content
> > by . If the downstream 02 sensor  switch points stays  high, the
upstream
> > 02 sensor goal  voltage will change and  allow a low 02 content.
> >
> > Glenn Beasley
> > Chrysler Tech
>
> For now, I defer to you on this Glenn.  I had read thru the description
> of the O2 sensor operation several times in the FSM (though I know they
> don't always tell the whole story), and forums that I have read that it
> is discussed on, it is stated like I said.  I will re-investigate and
> re****t back.  But you're probably right.
>
> Bill Putney
> (To reply by e-mail, replace the last letter of the alphabet in my
> address with the letter 'x')

The factory service manual does not get into details as our student
handbooks do. I save every book I get and refer back to them on many
occasions. When I read this post it brought back some of the stuff we
talked
about in class long ago.

Glenn