fwiw..
I had a not-that-old 02 sensor acting up.
Unplug it ..van runs fine.
a new one fixed it nicely.

they run amazingly well without an 02 sensor input ..
just a lot smoother with.

and the suggestion to cycle the key off and on quickly is a very useful
technique ..
both to keep moving and it is diagnostic information.

for fun ..
if I ever need to , I think I'll unplug the ECU and 02 sensor ..
the ohm check between the 02 sensor signal wire and its shield ..
looking for any short there.
I have seen a harness or two where the original 02 sensor coax was cut off
near the ecu ..
and a new one spliced on.
I have not seen one shorting out yet actually though, not yet anyway , but
I'm sure it's very possible.

Scott
----- Original Message -----
From: "tom ring" <taring@TARING.ORG>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Friday, December 09, 2011 5:56 PM
Subject: Re: The Vanille Shake Syndrome

> Absolutely.
>
> Sometimes it's the connector to Temp Sensor 2, sometimes it's the sensor
> itself.  My '85 has done both.
>
> Clean the connector really well with contact cleaner, then with something
> gentle to medium abrasive, then flush well with contact cleaner to flush
> out
> any abrasive left.  Wait for the cleaner to evaporate.  Help it along if
> you
> want to.  Be careful if it's flammable cleaner.
>
> If that fixes it, great.  If not I'd try a new sensor.  They're not free
> but
> aren't bad pricewise.
>
> And I have an O2 sensor issue, I think.  But I'll leave that open until
> after
> New Year's Day as I won't have time to address it before then.
>
> tom
>
> On 9 Dec 2011 at 16:51, Ken Lewis wrote:
>
>> Peter,
>> Tattoo this somewhere prominently:
>>
>> Always suspect the TEMPII sensor.
>>
>> Ken
>>
>> ----- Original Message -----
>> From: "Antony P Marsh" <apetermarsh@ME.COM>
>> To: <vanagon@GERRY.VANAGON.COM>
>> Sent: Friday, December 09, 2011 12:47 PM
>> Subject: [VANAGON] The Vanille Shake Syndrome
>>
>>
>> > Dear Readers
>> >
>> > Sorry to bother you but up against what appears to be the Vanagon
>> > syndrome.  After starting from cold the engine runs OK but when it gets
>> > warm it coughs and splutters, seems to be missing and barely gets to 2K
>> > rpm.
>> >
>> > Wondered if you have any ideas or suggestions?  Here is what we have
>> > done
>> > so far.
>> >
>> > Replaced the gear shift linkage nylon balls and other parts and the
>> > shifting is like new, smooth, precise and is excellent.  The soup spoon
>> > gear lever is no more.  Thank you to Dennis Haynes for his diagnosis
>> > and
>> > Ken Wilford for his fast sending of the necessary "bits".
>> >
>> > Replaced 02 sensor with new Bosch sensor with three lead attached -
>> > made
>> > no difference.
>> >
>> > Replaced the very red rusty fuel tank, all ensuing fuel hoses attached
>> > to
>> > the tank, new Bosch filter. The fuel pressure is excellent (35 lbs) and
>> > the fuel is no longer rust colored - made no difference.
>> >
>> > We discovered a pig-tail already installed in the engine which looks
>> > like
>> > it has been there a while.  I have another that I tried - alas no
>> > change.
>> >
>> > Discovered a crack in the distributor body - on removal - the crack
>> > turned
>> > into several separate pieces.  Thinking this was it - replaced it.
>> > Still
>> > the same.
>> >
>> > All the spark plugs are new Bosch, adjusted correctly.
>> >
>> > What I can't get over is how well the van ran on my way northern
>> > Florida,
>> > power was great, 70 mph was no effort and I was checking milage at 20
>> > mpg
>> > running the AC.  Then it started with the cough - still sick......
>> >
>> > Kindest regards
>> >
>> > Peter Marsh
>> > Naples FL
>> > 239 595 6171
>> >
>>