Date:         Sat, 20 Aug 2011 23:24:26 -0500
Reply-To:     John Rodgers <inua@CHARTER.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         John Rodgers <inua@CHARTER.NET>
Subject:      TJ Hannink does it again! Throttle Switch Adjustment
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

  For me, this was so good, I just had to share.

Tim Hannink came over again this past Thursday, this time to rescue me
from myself. The issue was the throttle body and how to adjust the
throttle switch.

After overhauling my AC system, and resetting the idle speed, the engine
didn't run right. Past e-mails from many - Dennis Haynes, Scott Daniel,
and others - all said to check and if necessary adjust the throttle
switch before doing much else. Well, it got done in the process, and
sure enough the switch was not set right.  Anyway - If the throttle
switch  was right, then most other things will follow. Well, I read the
Bentley, and I read the Haynes, and I read the VW Digifant Service
Manual. It just didn't come through to me how to do this. It just looked
like a big bugger-bear problem that I could screw up somehow. That
switch is mounted UNDER the throttle body and surrounded by a lot of
stuff - hard to get  at. Well - Tim Hannink to the rescue.

While I watched, hoping to learn, Tim removed the air filter box, the
AFM, disconnected all the hoses to the AFM and from the idle stabilizer
valve, disconnected other things attached to the throttle body, and in
less than 5 minutes had the throttle body exposed so that all that was
left were the two attaching screws holding the throttle body to the
engine. The screws were loosened, and the throttle body was out. It was
nasty with grease, oil, and road grime and dirt. The throttle switch was
removed from the throttle body, and with a scoop of the hand into a can
of GOJO hand cleaner, a gob of cleaner was smeared around and it the
throttle body, and it was given a serious scrub using a toothbrush. In
just a few minutes all the corruption was emulsified and was wiped away,
using rags leaving the throttle body very clean. After cleaning the
throttle switch was reattached, and using the allen set screws, the
upper and lower limits for the switch were set up using the ear -
listening for the slight click when contact was made or broken. No
feeler guage was used, though one could. Once the contacts were set, the
set screws were tightened, the throttle body re-installed in reverse
order. After re-assembly, the engine was started and ran perfect! With
one exception which I will address further down. I could not ask for
better running. Big KUDO's to Tim for this one!!

My point in writing all this is (1) to publicly thank Tim for his help
for showing me how to do this in a quick and easy way and (2) to say
that all of us who own Vanagons should know how to do this. These vans
are unique vehicles, and those who truly know how to work on them are
few and far between, and getting fewer. The throttle switch adjustment
is extremely important, is as easy as falling off a greased log (well,
almost) and therefore each of us should know how to do it. It isn't hard.

Finally, to the remaining issue. Even though we went through every step,
When the idle stabilizer valve connector is connected to the ISV, the
engine over revs. Disconnect it, and rpm drops back to normal. Tim nor I
could figure this one out. If anyone might have a suggestion about this,
I'm all ears.

Thanks,

John

This is a repost, since Gerry went down and it didn't get posted.

I went back and read what Dennis Haynes recently said about why the
engine will over speed. I have not had a chance yet to check voltage
from the Temp II sensor, but if that is wrong the ECU will attempt to
speed the engine. Got a little more checking tp do then. Love the way it
runs, though, without the ISV in the circuit

John

--
John Rodgers
Clayartist and Moldmaker
88'GL VW Bus Driver
Chelsea, AL
Http://www.moldhaus.com