Date: Mon, 16 Jun 2014 06:20:26 -0700
Reply-To: Don Hanson <dhanson928@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Don Hanson <dhanson928@GMAIL.COM>
Subject: Re: Vanagon Syndrome is it also known as Digifant Disease, maybe?
In-Reply-To: <CA+r=JhpmnLd3Buv9_-P3DRvhf62+ugM=rA1_oPwDZZPcpJS7tA@mail.gmail.com>
Content-Type: text/plain; charset=UTF-8
On Mon, Jun 16, 2014 at 4:35 AM, Larry Alofs <lalofs@gmail.com> wrote:
Don,
Could you clarify what you mean by MAP? Classical vanagon syndrome
refers to a mechanical vibration of the wiper arm in the air flow meter
(AFM). The resultant stumbling, etc. shows up after traveling at a steady
speed on the highway for a while. The term has "Vanagon Syndrome" has also
ben applied erroneously to various other ailments.
The abbreviation MAP leads me to assume that you have a mass air flow
meter which uses a heated wire instead of the moving vane in a vanagon AFM.
If so, your problem is unrelated.
Could you tell me the difference between Digifant I and II ?
Have you checked the throttle switch with an ohmmeter?
Larry A.
I am not very familiar with all the internals, parts and the mechanisms
of the EFI.... Mine have never really screwed up and so far I've had no
need to learn about them. I'm calling what must be the AFM a Manifold Air
Pressure device, I guess that was wrong... The Flapper door in the inlet
that sends the signal from the arm to the brain...that's what I was
referring to, erroneously, as the MAP...
Your description of how the running problem occurs is exactly what I
have begun seeing, suddenly, just these last few days. It's occurred (so
far) after a sustained highway run. What I find odd is there was no
inkling of this problem prior to it happening. Most problems seem to show
some slight warning signs, some preliminary minor glitches before they
become BIG problems...This one no......this motor has always run cleanly,
smooth and flawless until now...
I can't tell you what the difference is between D-I and the D-II. The
Bently for my Cabriolet '92 motor's engine management says Digifant
II...I've no other experience with VW engine management systems. Never had
a WBX motor to mess with...The air cleaner and AFM I do have on this motor
is from the original 84 Vanagon. I am assuming the Cabriolet, Jetta, Fox,
Rabbit has an identical AFM system but with 'plumbing' configured to fit
into the front of one of those cars.......All the other stuff, the sensors
and switches etc..., that I've replaced over the years, so far all those
have always been interchangeable with a Vanagon, so I am hoping this
problem is also 'interchangeable' .... maybe it is Vanagon Syndrome..
I have not done any digital volt meter readings anywhere. I'm really
not very good at that type of diagnostics, I seem to do better at deducing
the cause of a problem (often with the help of you guys here on the Vanagon
forums) isolating my problem by plugging or unplugging something, and then
and swapping in a new part.
I did(so far) just clean all my sender connections with contact cleaner
and compressed air and give them a spritz of WD 40, while the motor was
idling. I got no change in it's perfect idle..I 'clicked' the TP switch
and that altered nothing either.
If there is any 'gross' method to determine the cause and go about fixing
this, it's more my style..I really don't "do" Ohms and millivolts off a
meter very well. But if I have to, I guess I will learn.
I have recently been messing with a GM Safari OBD widget and while it's
pretty neat-o to see all those fancy numbers on the LED readout...I don't
much like doing it...
Thanks in advance for any advice..
Don Hanson
I don't need to know that for sure, though I have also wondered, in
passing, what is the actual difference between a Digifant and a Digifant
II...
I just need to fix what I have, what has been working excellently now for
about 5yrs but is now exhibiting weirdness..
I have not yet done any
| 
