Along with Davids comments I'd suggest visually inspecting the inner
lead of the O2 green coax near the connector on body portion of
harness. I see the warm start issue was present before the O2 sensor
was swapped out, but a break at the inner wire casing can allow
strands of the coax shield to touch the centre lead. This fault could
be intermittent. A little WD40 makes it easy to slide back the rubber
boot at the connector.

Neil.

On 11/19/16, David Beierl <dbeierl@attglobal.net> wrote:

>
> Oxy sensor shorted to ground is the other huge villain (along with
> Temp-II) giving super-rich operation, but even on a warm start that
> shouldn't have any effect at the moment of starting; it kicks in 30
> seconds or a minute later, just long enough to get from the motel
> parking lot to the road before it suddenly hates idling.  Still, I
> suggest with any running problem at all to disconnect the sensor,
> check that the line isn't grounded (should see ~.45 volts on the ECU
> side with a digital voltmeter), and leave it disconnected until the
> engine is running properly.  The only thing that needs it is the
> catalytic converter, and it can really mess you up.
>
> Yrs,
> d
>

--
Neil n

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