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Subject:Re: 2.1 WBX Warm Start Troubles
From:David Beierl
Date:Sat, 19 Nov 2016 20:02:27 -0500

At 18:15 11/19/2016, Michael Magnani wrote:
>Key ON, Engine at idle: 32 psi

That's still only eight inches vacuum at idle.  Bentley thinks you
should have sixteen, and I'm used to seeing 13-14 on my 2.1l (and you
can get this more directly and with less gasoline involved by teeing
a vacuum gauge into the brake-assist line on the engine side of the
check valve).

But vacuum leaks ought to give lean operation at idle, not rich; so
even though this needs solving I don't see it as your rich-starting issue.

To clarify the situation I'd swap in another ECU just to see if
anything changes.  You've checked that the injectors aren't leaking
down, correct?  Have you checked the injector spray pattern?

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