Date: Mon, 16 Jun 2014 07:35:59 -0400
Reply-To: Larry Alofs <lalofs@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Larry Alofs <lalofs@GMAIL.COM>
Subject: Re: Vanagon Syndrome is it also known as Digifant Disease, maybe?
In-Reply-To: <CAHTkEu+zP8k4UkSCScUT1fJ5PY=mKc5Rh5MyGwRdVE=snZ5t9A@mail.gmail.com>
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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.
On Sun, Jun 15, 2014 at 11:40 PM, Don Hanson <dhanson928@gmail.com> wrote:
> I've seen mention often of the Vanagon Syndrome but I only skimmed the
> threads, thinking.. that doesn't apply to me, my Vanagon doesn't have the
> WBX motor, it has an inline VW four from various Jettas and Rabbits.
> However, mine runs most of the same Vanagon stuff..the MAP, the air
> cleaner, same idle control, similar throttle switch, same Temp II, etc...It
> runs Digifant II, just like a WBX Vanagon, I guess..
>
> My motor has always run really sweet...never hardly ever any hickups or
> misses or anything but in the past two days it has decided to act up. It
> may be this Vanagon Syndrome, that is all I can come up with really.
> Coming home from windsurfing yesterday I blasted along the Columbia into
> about 50mph headwinds for about 50 miles with nary a thought for the
> motor...It just ran smooth and strong as normal until I got out to open our
> gate...then it went all wonky...missing like a poorly tuned carburetor
> motor...though I 'jazzed it' with the accelerator and made it to the
> garage. I checked the normal stuff this morning, connections, fuel pump
> sprayed the throttle switch...and let the motor idle for almost an hour
> without it missing a single note... Weird...
> This afternoon I again went 50 miles to windsurf and when I got to my
> turnoff...again the motor got "sick"...until then, very sweet..I nursed it
> to the launch site..about 1/4 mile, and saw nothing on any of the gauges
> out of the normal range no warning lights no weird sounds...After my
> session on the river, the van started and ran 100% normal again and again I
> blasted into the headwind all the way home without any acting up this
> time....
>
> So twice in the past two days I have had short interludes of really
> crappy running...followed by normal running again. I can't induce the
> behavior by wiggling wires or flicking the throttle switch or blipping the
> throttle or anything.
>
> Now I recall that maybe there is a fix...something to calm down the
> signals to the Brain? Prozac for the Digifant? A resistor or
> something?
>
> What do you think? Anyone want to chime in with advice or information
> that might help me here? The Fuel pump is just a month old and sounds
> normal..the filters are new also...It did behave a little like bad gas, but
> only for those two interludes...the rest of the time, perfect running...My
> fuel consumption has not changed nor have any of my gauge normal ranges..
> No visible smoking from the exhaust... Got me puzzled as to where to begin,
> other than the vague recollection of similar symptoms being mentioned as
> Vanagon Syndrome...
> Thanks, Don Hanson
> 84 van, 92 Jetta 8 valve head, 93 Jetta ABA bottom end, digifant II
> operating system.
>
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