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Subject:Re: Can O2-sensor make engine run too lean?
From:David Beierl
Date:Thu, 22 Dec 2011 00:53:32 -0500

At 12:15 AM 12/22/2011, John Lauterbach wrote:
>Any suggestions on next steps?

Unplug it again, stick a digital voltmeter* on 2-volt scale on it and
see how it behaves as engine warms up.  If you play with the throttle
and can get it to show different voltages between about .2 and .8
volts it's likely ok.  If so leave engine running and connect back to
the ECU while voltmeter still connected.  The meter*should*
immediately begin showing random changing readings, and if there's a
bar graph it should be cycling up and down with a period of a few
seconds at idle.

Report back results...

*Ideally a high-impedance analog meter like a VTVM, but not likely
you have one.  But if the digital has a quick-acting bar-graph
display that would be nice.

Yours,
David
ps - a contaminated sender can fail in a very short time - minutes or less.