Date:         Fri, 26 Sep 2008 12:12:18 -0500
Reply-To:     Larry Alofs <lalofs@GMAIL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Larry Alofs <lalofs@GMAIL.COM>
Subject:      Re: Question about testing O2 sensor with digital meter
Comments: To: Jim Felder <jim.felder@gmail.com>
In-Reply-To:  <4d1b79350809260937w1bb3f0faw3d7b3c8b7f826d43@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1

Jim,
  You didn't say whether you had the O2 sensor disconnected from the harness
when you made this measurement.  If so, the reading is reasonable.  With no
sensor connected, the ECU will make the system run rather rich and the
unburned hydrocarbons in the exhaust cause the O2 sensor to give this high
reading.  fuel>voltage
  It is best to try to monitor the voltage while the sensor is connected in
the system with the computer in closed loop operation.  Then you should see
the voltage swing back and forth between about 0.1 volts and 0.8 or 0.9 v.
It shouldn't take more than a second or two to complete a cycle at idle.

good luck,
Larry A.




On Fri, Sep 26, 2008 at 11:37 AM, Jim Felder <jim.felder@gmail.com> wrote:

> I'm having a recurring nightmare with my 2.1.
>
> Was dying after first 30 seconds, overly rich like it was the O2
> sensor. I replaced the O2 sensor with a good used one. It ran fine for
> a week, then started the same thing. So, I swapped out the ECU and
> temp 2 sensors. No help.
>
> When I test this second O2 sensor, I hook up my digital meter (set to
> 2v) and it starts out at zero as the car warms and eventually tops out
> and hovers (at idle) just over .800.
>
> Is this right?
>
> Jim
>