idle air bypass screw

[rick@brubakerbox.com (Rick Alexander)]

Your lack of a Bentley is showing here. Dwell is a measure of any on/off
cycle. In this case you are measuring the idle stabilizer voltage not point
angle. By the way dwell as it applies to points is only a reflection of the
gap of the points it is actually the duty cycle.

Rick Alexander
http://www.brubakerbox.com
http://clubs.hemmings.com/hams/
http://clubs.hemmings.com/vwsrus/

----- Original Message -----
From: <cwass99@rogers.com>
To: "T. Reed" <treed2@u.washington.edu>
Cc: <scirocco-l@scirocco.org>
Sent: Wednesday, March 27, 2002 9:55 PM
Subject: RE: idle air bypass screw


> Hi,
>      I'm sure others will respond, but I don't see them yet...;)
>      I don't have a Bentley yet (still, I really have to pitch a bitch at
the
> book seller) but I don't see what playing with your idle speed has to do
with
> the dwell angle.  The idle adjust screw (guessing it has the same effect
as the
> one in my 8v) just tweaks the idle speed.  Dwell is the amount of
distributor
> rotation (expressed in degrees) that the points would be closed (I could
be
> backwards here, it's been a very long time since I've adjusted points,
bigger
> points gap = smaller dwell angle, right?).  That duration of points
closure
> won't change if the engine is idling faster.  If there's 30 degrees
(guessing
> here ;)) dwell angle at 750 rpm idle, there will still be 30 degrees dwell
angle
> when idling at 1200 rpm.  Does your 16v even have points?  I'd bet against
it,
> so I'm not completely sure what the reading would mean with a Hall sender
and
> electronic ignition.
>      I can't comment on the hoses.  Never even looked seriously under the
hood
> of a 16v :)
>
> Cheers,
> Colin
>
> On 27-Mar-2002 T. Reed wrote:
> > Hey all,
> >
> > Well with my sticky fuel plunger being unstuck, its time for some
'tuning'
> > (ooh- that sounds so ricey nowadays.) and I'm going to start with the
> > idle screw on my throttle body.
> >
> > I've got a dwell meter and I hooked it up to the grey/blue wire as
> > indicated in the bentley.. but I couldn't quite figure out what the deal
> > was. Turning the idle screw wouldn't change the dwell reading at all.
Does
> > the car have to be warmed up (ie. cis-e operating in closed loop) for
> > this?
> >
> > The picture of the crankcase ventilation hoses in the Bentley are from a
> > left-hand-intake 16v and the hoses are a little different. Which hoses
are
> > they referring to as the ones you have to remove? The huge one coming
off
> > the block, obviously, but what about the small one that plugs in to the
> > side of that one? There is no such hose on my car - but there is a
little
> > nipple that hooks on to the bottom of the cold start injector .. and the
> > other end of that huge hose goes to the airbox.
> >
> > What about the small hose that goes from below the lower intake manifold
> > to the rubber intake boot? It seems like unplugging it would create an
> > enormous vacuum leak (like what happened when I unplugged the nipple on
> > the large hose going to the cold start injector fitting)..
> >
> > Is it really necessary to unplug all this crankcase ventilation shat in
> > order to get a good reading? Anybody know alternative methods of setting
> > the idle air bypass screw?
> >
> > Thanks,
> >
> > -Toby
> >
> > --
> > '87 16v
> >
> >
> >
> > _______________________________________________
> > Scirocco-l mailing list
> > Scirocco-l@scirocco.org
> > http://neubayern.net/mailman/listinfo/scirocco-l
>
> --
> Cheers,
> Colin
>
> If you can read this line, you're probably not illiterate.
>
>
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