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Subject:Re: Cold Engine Problem
From:Mark Keller
Date:Wed, 3 Jan 2001 09:53:27 +0000

Ok David,

I understand.  Then I would remove the air cleaner and AFM assembly and
check for free movement of the AFM vane.  The vane is connected to the
wiper arm which generates the signal to the ECU for more fuel.  If you
have an ohmmeter a couple of easy test are the resistance behavior as
the wiper is cycled and the resistance of the air temp aka Temp I
sensor.  These items fit your observations too.

 But low fuel pressure would also be a consideration. It's always a good
idea to confirm the Temp II sensor; most people replace these as whether
it needs it or not whenever the Fuel Injection starts to act up. They're
cheap $10 or so and  if your handy  you can literally  pull the old one
out quick and put the new one in fast, and lose a cup of coolant.

Sincerely,

Mark Keller
91 Carat
"MOST,DAVID" wrote:
>
> >
> > You said the engine essentially has a delay in throttle response when
> > cold; and the last cold engine experience was not a delay but rather a
> > stalled engine.
> >
> The first part is correct...a delay followed by a bit of sputtering.  The
> last experience was no response at all from the pedal, BUT it continued to
> idle. I'm not sure if it would have stalled, but as I started to roll
> backwards, I applied the brakes and after a couple of seconds, I turned
> the engine off.  Then, it wouldn't start again.  I hope this slight
> correction is helpful.
>
> > I would check the fuel pressure 29 psi at Idle 36 Psi at low vacuum.  On
> > a cold engine the computer assumes the fuel pressure is set and gets no
> > feedback if the mixture is too lean or to rich.  If the fuel pressure is
> > low then the engine runs lean and would stay that way until the engine
> > warmed up, and then the O2 sensor would cause the injector pulse to be
> > lengthen until the mixture was correct.
> >
> Thanks for the thoughts Mark.  I'll let  you know what I discover.
>
> David