Date: Wed, 25 Jun 2014 19:37:52 -0600
Reply-To: OlRivrRat <OlRivrRat@COMCAST.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: OlRivrRat <OlRivrRat@COMCAST.NET>
Subject: Re: Inconsistent stumbling on resume throttle..Was "vanagon
syndrome?"
In-Reply-To: <CAHTkEuJnkqu0-VsHHCSy7QGkSPE7PJ503sJad188i-RfAgrQ9A@mail.gmail.com>
Content-Type: text/plain; charset=windows-1252
Don
So just to be ReallyClear on this ~ "upstream of the O2 sensor" ~ So the crack is
between the Eng' & The O2Snsr ~ If this is indeed the Case it is NOT a good thing for
your Eng's Performance or your O2Snsr ~ RawAir is MostLikely being pulled through the
crack into the Pipe & Causing the O2Snsr to think it is being exposed to LeanExhaust so
the ECU would then dump gas into the Mix to compensate & when you back off the Gas
it is conceivable that an ExtraShot of RawAir might get sucked in through the Crack &So
when you get back on the Gas a very Rich, maybe even FloodedCondition, is occurring @
which point the ECU just says ~ OK this is Goofy, I need a short break ~
The Iffy Wires may indeed be contributing to the Issue but
~~~~~~~ YouReally NeedToFix ThatCrack ~~~~~~~
& ~ Your O2Snsr should not be in 1 of your HeaderTubes ~ It should be located after
the Collector so that It "Sees" the Exhaust from All4 Cyl's ~
ORR ~ DeanB
On 25 Jun , 2014, at 10:24 AM, Don Hanson wrote:
> more...I may have the culprit...
>
> I removed my O2 sensor, which was a Denso Universal..It was adapted, with
> the Denso junction plug.... into a long flat VW plug on the motor end of
> the harness...4 prongs...3 from the O2 sensor to the brain and one (grey)
> from the harness plug to a ground nearby.
> Of the three coming FROM the O2 sensor (two white, one black) the black
> lead was almost completely broken...or maybe it was and just touching now
> and again... So that may have been the problem, certainly it was not
> functioning properly in that condition..
> The O2 sensor itself: It looks pretty strange in that it was covered
> with soot, most likely from idling while the exhaust warmed up to get it
> removed, but under that thin soot, there was a thick caked white deposit
> covering the whole element...I don't know what these are supposed to look
> like but that doesn't seem right.
>
> So I have a new Bosch sensor..two whites and a blue with a round plug...I
> am going to splice that into the VW flat plug...putting the blue to the
> black and the white to white...the grey will go back to the block where it
> was before.
> The Bosch sensor is different in that it has a perforated cylinder
> covering the element, I guess..but I think I got it as a specific VW
> sensor...
>
> I also found in my parts collection a good Temp II sensor (tested as per
> the Bently) a new red Bosch coil and an underneath throttle switch...(I
> think..on the inline VW motor the switch is 'concealed' below the throttle
> body...
>
> I am first going to change the O2 sensor and the Temp II sensor, see if
> that does it...
>
> Anyone have any comments?
>
> On Wed, Jun 25, 2014 at 12:08 AM, Dennis Haynes <d23haynes57@hotmail.com>
> wrote:
> The symptoms clearing after cycling the ignition switch is classic of a
> problem with the O2 sensor or circuit. Sensors do get intermittent and they
> are easily fouled by road stuff on the outside and worse oil or antifreeze
> on the inside. Rich mixtures for any reason can also cause them to carbon
> foul.
> On the Vanagon Digifant another common problem is a bad ground for the O2
> reference circuit. One of these connections is the ground wire in the
> harness to the distributor. Check the archives. I have written the
> procedure to test the O2 sensor wiring in the past. If it can’t be found I
> can re-write.
>
> Dennis
