Date: Thu, 19 Aug 2010 14:36:14 -0700
Reply-To: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject: Re: AFM track cleaning wisdom
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reply-type=response
now that we know it's a 2.1 ..
which fuel system , the 1.9 original one, or a full upgrade to the 2.1
Digifant ?
Though I can say that is especially actually an upgrade over the 1.9 Digijet
..
but one can run a 2.1 block in an 85 vanagon ..
and run almost any combination of 1.9 or 2.1 bits in the exhaust system,
cooling system, and engine management system.
what I run currently in an 85 Adventurewagon is 2.1 block, full 2.1 exhaust
system, 2.1 intake runners and plenum and throttle body ....but all the rest
is 1.9 Digijet. Runs just great.
btw ..
seems to me people often think 'component ...
and so often it's not.
just had one yesterday, 1.9 in an 84 Westy ..
fast erratic idle ..just seemed ragged generally.
I only spent a few minutes looking at it and discovered the stud that holds
the right side of the cross-over heater circuit metal pipe on top of the
engine, was broken off, resulting in a nice hole in # 2 intake runner.
guy called today and said fixing that made a huge difference.
once again ..
'a blockage or leakage of fluids or electrons, and it wasn't a component .'
also ...*Visual Inspection* ..
One could/should pretend one is Sherlock Holmes or Monk and 'just look' ..
just look and look and look and see what you see visually.
there are often many visual clues. Like look at and touch every little
thing you can see or think of ..
there are a lot of clues there if you can just see them.
often people post 'my van does X ..what do people think is the problem? '..
I'm always like 'well, did you LOOK ?'
lol. I've had people bring in a car for a horrible noise ..
and they never even LOOKED at the engine to see some big ole hose that fell
into fan belts or whatever.
so always just LOOK ...look at details and for clues.
and whatever has been messed with or worked on ..
look extra carefully at those.
workmanship mistakes are fairly common actually.
----- Original Message -----
From: "A. Hurley" <ahurley@SHOPVIEWIT.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Thursday, August 19, 2010 6:50 AM
Subject: Re: AFM track cleaning wisdom
> I've been reading up on this - preparing to up the big grade to
> Lewiston today.
>
> I went over the engine last night and noticed the lid to the AFM on my
> 85 Vanagon just came right off, revealing the wiper blade, etc.
>
> It's a pretty new 2.1 engine in the 85 Vanagon.
>
> Andree
>
>
>
>
> On Wed, 11
> Aug 2010, Karl Wolz wrote:
>
>> IIRC, you have an '85? I was told that the capacitor fix only worked on
>> the
>> digifant system, so if you have the original digijet 1.9L, the capacitor
>> fix
>> will do you no good. My engine used to cut out just as you're
>> describing,
>> especially after a long high speed run or after a stiff limb (or during).
>> Quite aggravating. We never did find the reason for the cutting out, but
>> it
>> is well chronicled at VW dealerships, though most have probably forgotten
>> the issue by now.
>>
>> One dealership mechanic was convinced that the problem (which occurred
>> while
>> the van was still under warranty) was poor grounding; he installed one
>> ground strap after another, to no avail. We replace the ECU, the AFM,
>> countless ground straps and other electronic parts. Eventually, we
>> replaced
>> the entire engine and the problem went away. No one was ever able to
>> adequately diagnose the issue.
>>
>> Oh yeah, we did clean the wiper track in the AFM - no joy there either.
>>
>> Sorry,
>>
>> Karl Wolz
>>
>> |-----Original Message-----
>> |From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf
>> Of
>> |Mike "Rocket J Squirrel"
>> |Sent: Wednesday, August 11, 2010 3:59 PM
>> |To: vanagon@GERRY.VANAGON.COM
>> |Subject: Re: AFM track cleaning wisdom
>> |
>> |As I mentioned, I had the thing open a few years ago and moved the wiper
>> |to a fresh portion of the track. I did this as you describe: by ovaling
>> |the mounting holes, so I phrased it wrong, I didn't move the wiper but
>> |the track. My bad.
>> |
>> |I've only put about 15,000 miles on the thing since, I doubt the wiper
>> |has worn through the new portion of the track yet. But I will inspect
>> |and report.
>> |
>> |I'm following up on the mechanic's suggestion as he felt that the
>> |symptoms I described last week (see "Mystery engine cutouts") may be due
>> |to a bit of schmutz on the track.
>> |
>> |Anyway, in Ye Olde Days when I was a broadcast engineer, we used to
>> |clean the Shallco program attenuators (coined-silver contacts) with
>> |Hoppe's gun oil. That's probably a bit gummy for a AFM potentiometer,
>> |but there may be some other cleaner/preservative I can put on the track
>> |while I have it open.
>> |
>> |Mike S and David-The-B both point out that abrading the track with a
>> |pencil eraser is dumb, dumb, dumb. Point taken. See their posts for
>> |details.
>> |
>> |To David, thanks for mentioning that capacitor -- yes, I have a 22uF
>> |tant cap wired in to reduce wiper/track noise.
>> |
>> |Just for the record, Richard-K asks for general AFM track servicing
>> |information and says that he has "some `bogging' problems similar to"
>> |me. I want to say to Richard that I would not describe the problem I had
>> |as "bogging," more like an abrupt loss of power, mixture slamming toward
>> |full lean condition, ignition continuing, then after 3 to 4 seconds,
>> |abrupt return of full power.
>> |
>> |Out of curiosity, does anyone know what the ECU tells the engine to do
>> |if the AFM wiper loses contact with the track? Cut off fuel?
>> |
>> |--
>> |Rocky J Squirrel
>> |84 Westfalia: Mellow Yellow ("The Electrical Banana")
>> |74 Westrailia: (Ladybug Trailer company, San Juan Capistrano, Calif.)
>> |Bend, OR
>> |KG6RCR
>> |
>> |
>> |
>> |Tom Young wrote:
>> |> As I recall, and I may be wrong, the issue here with the AFM track
>> isn't
>> |> that it's dirty, it's that hours and hours of wear and tear at a
>> |> particular spot actually result in the surface material being etched
>> |> away, causing the ECU to think "Oh, the AFM's vane is closed!" and
>> |> reacting accordingly. So I'm not sure that cleaning has much to offer
>> |> here.
>> |>
>> |> I've had good results by opening up the AFM (air-cooled, and I'm
>> |> assuming the water-cooled engine's AFMs are the same), removing the 4
>> |> screws that hold the wiper circuit board, removing the circuit board
>> |> itself and then ovalizing the 4 holes in the board that the screws
>> pass
>> |> through. You can then re-install the circuit board in just a slightly
>> |> different position, giving the wiper a new track to pass over.
>> |>
>> |> Tom Young
>> |>
>> |>
>> |> ----- Original Message ----- From: "Mike "Rocket J Squirrel""
>> |> <camping.elliott@GMAIL.COM>
>> |> To: <vanagon@GERRY.VANAGON.COM>
>> |> Sent: Wednesday, August 11, 2010 2:30 PM
>> |> Subject: AFM track cleaning wisdom
>> |>
>> |>
>> |>> My mechanic dude suggested the the cause of the engine's periodic but
>> |>> brief loss of power during grade climbs last week might be a dirty
>> spot
>> |>> on the AFM track and suggested gently cleaning it with a pencil
>> eraser.
>> |>>
>> |>> I opened it once before, a few years ago, to move the wiper to a
>> fresh
>> |>> bit of track. I'll open it again to clean the track.
>> |>>
>> |>> Is the pencil eraser trick good enough, or would it benefit to use
>> some
>> |>> kinda cleaner?
>> |>>
>> |>> --
>> |>> Rocky J Squirrel
>> |>> 84 Westfalia: Mellow Yellow ("The Electrical Banana")
>> |>> 74 Westrailia: (Ladybug Trailer company, San Juan Capistrano, Calif.)
>> |>> Bend, OR
>> |>> KG6RCR
>> |>>
>> |>
>>
>
> Sincerely,
>
> Andree Hurley
| 
