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Subject:Re: O2 Sensor problem
From:David Beierl
Date:Sun, 22 Mar 2020 13:37:02 -0400

On Sun, Mar 22, 2020 at 12:25 PM mccullough bob <mbob1950@gmail.com> wrote:

>
> Probably kicking ECU back into open loop for bit?

Yes, exactly.  ECU ignores O2 for a bit after starting even if engine is
warm enough and sensor signals ready.  Temp-II OTOH acts even during
cranking.

I found that disconecting the o2 sensor wire solves this problem. Engine
> runs good. Revs normally and climbs hills well
> It is running rich as expected.
>

If everything else is in good shape it shouldn't run rich.

> With engine running and o2 sensor connected, Ive got 0.92 v  sensor to
> ground.
> Running and O2 disconnected   .91v on sensor and .44v on harness to ECU
> Sensor wire is not shorted to ground. o2 heater has 12v
>

Unplug the heater and see what happens to sensor voltage.

Yrs,
d