I disagree.  With the engine warm, a properly working O2 sensor connected to
the ECU should show a voltage that goes up and down between one or two
tenths of a volt and nearly one volt.  This should happen about once every
second or two at idle, faster at higher RPMs.

Wes:
  You didn't say what was connected when you did this test.  To show normal
behavior, the O2 sensor must be connected to the ECU when you monitor the
voltage.  They work together in the "closed loop" operation.
  It is also important to use a meter with a high impedance so that it
doesn't affect the voltage that you are trying to measure.  Most digital
meters are OK; most analog meters (with a needle) are not OK.
  If I recall you have a 1.9.  If it has the one wire sensor with no heater,
you need to be sure it is thoroughly warm for the sensor to operate
properly.

Larry A.

On Fri, May 16, 2008 at 5:02 PM, Taeke Takeon <taeke.t@gmail.com> wrote:

> O2 sensor isn't active at idle, or rather the lambda FI computer isn't
> active.
>
> On Fri, May 16, 2008 at 5:53 PM, pickle vanagon <greenvanagon@gmail.com>
> wrote:
>
> > Just for fun, I decided to go out and "test" my oxygen sensor today, by
> > which I mean I warmed up the car, and then checked the voltage coming off
> > the sensor wire with the van at idle.  I got readings of around .52
> volts,
> > which maybe seems okay (?), but the voltage was steady, not oscillating
> (it
> > stayed between .51 and .53 volts always).  Does this mean my engine is
> > never
> > entering closed loop operation?  If so, what are the standard things to
> > check, since the O2 sensor seems okay?
> >
> > Thanks,
> > Wes
> >
>