Date: Thu, 17 Jun 2004 01:11:56 -0400
From: Michael Tiefenback <tiefenback@domain.elided>
Subject: [alfa] Re: hot restart and throttle comment
Date: Wed, 16 Jun 2004 21:18:54 -0600
From: C M Smith <cmsmith@domain.elided>
Subject: [alfa] Hot restarts on V6 engines
Supposedly, opening the throttle on a FI engine has no effect
while cranking.
just before gleefully supplying a couple of interesting counter-examples.
I'd suggest a _possible_ mechanism. FI engines monitor air flow and
coolant temp and maybe another thing or two to set mixture for
running/starting. A fully hot engine makes the ECU lean out the
engine. If the false air leaked around the AFM by the idle CO screw
dilutes the mix more with only starting RPM
(say, because a sticky AFM door doesn't want to open) then opening
the throttle would pull more air through the AFM, opening the door
or simply diluting the effect of the idle CO false air. Maybe.
Pushing a bit of carb/brake cleaner into the intake of the balky
warm engine might show whether it's rich or lean.
Or not. Such a test might indicate what to tweak for improving the
warm start behavior if it is a nuisance (say, to a spouse; I've
learned that my spouse isn't as handy with or tolerant of funky
mechanicals as I usually am).
Michael