BTDT. I had a problem that started out with intermittent Had a similar
problem and basically started at the engine and verified that I had proper oil
pressure and that both switches are working properly. In a nut shell; you
can  disconnect the 2 wire connector that has the wires running from each
sensor and  both connected to the rest of the wiring harness at a connector
near the coolant  distribution tower. (check your bentley for specifics on wire
colors). There are  two switches that work off of grounding that are
attached to the 2 wire  connector. One will light a test light that receives power
at the alternator and  that light should go out when the engine is started.
The other switch has the  light out and will light it when the engine is
started. In short, what is lit  goes out and what is not lit lights when
proper engine oil pressure is realized.  Don't remember which is which right now
so check Bentley or some one on the list  will chime in. Verify that you
have proper oil pressure first and then move onto  wiring and connections. My
problem ended up being the t14 connector at the dash  cluster. It relies on
the structural integrity of part of the plastic that forms  the dash cluster
housing to give a good contact from the connector to the  ribbon. On my van
one of the ears that holds one of the sides of the connector  on. Use care
handling the cluster as it will be very fragile and brittle from  the age and
heat. If you have established that the switches are working properly  and
the connections are good then you may have a problem with the L-board (see
Mark Drillock's recent posts on this). Of course having the proper Mann or
Meyle  oil filter and the correct grade of oil is a prerequisite to insure
that the system works properly It's a really fairly simple system to
troubleshoot. Good luck and use the Bentley if you have any questions on how the
dynamic oil pressure system works.

David Clarkson
90 Westy

In a message dated 12/11/2010 4:50:33 P.M. Eastern Standard Time,
syncronicity1@GMAIL.COM writes:

Well,  this is follow up from my post a few days ago (below).

So, last weekend  I drained and refilled with 20W50.  I thought all was
going
to be  good, went a good long distance on the test drive (to where my son
is
working at the christmas tree "store" in the mall parking lot).   All was
well, but then suddenly on the way home the oil light/buzzer came  on again.
But this time it took much longer, maybe 10-15 minutes.   Once it was on, it
behaved like before, kind of on-and-off depending on  driving conditions.

So I got a Mann filter, haven't installed it  yet.

And then an urgent trip came up today, we have to get a tree,  now!  "Ok
honey, I'll risk it with the van".  (What we do for our  babes is just
amazing isn't it.)  So I just took the exact same trip  as I mentioned above
to the Xmas tree store at the mall and back  again.  No oil light / buzzer
at
all.  Van just sat in the  driveway between these 2 trips, maybe the oil
rested and matured and is now  ready to behave.  Kinda like putting your kid
in "timeout".

So  this is getting puzzling.  I will still put the Mann filter on today
and
then more extensive test drives tomorrow.

Roland

On  Thu, Dec 2, 2010 at 7:21 PM, John Rodgers <inua@charter.net>  wrote:

>  I would drain the oil, install a Mahle or Mann oil  filter, refill with a
> good brand of 20W50 or 15W50 Mobil One or good  diesel 15W40. If that
doesn't
> fix it, you may have an internal  problem, but if things were good before
the
> oil change, this should  probably fix it.
>
> John Rodgers
> Clayartist and  Moldmaker
> 88'GL VW Bus Driver
> Chelsea,  ALHttp://www.moldhaus.com
>
>
> On 12/2/2010 6:48 PM, Roland  wrote:
>
> Hello folks,
>
> Very odd, the oil pressure  light comes on after about 7 minutes of
driving.
> 1989, 2.1 WBX.   It happens every time.  If I let it sit, and get half-way
> cool,  then it takes about 2-3 minutes for the pressure light/buzzer to
come
>  on.  I think the timing is associated with the oil warming up.  This  has
> never happened before.  I recently did an oil change, so  maybe...  And I
> have been doing some studying in the  archives.  So, I had bought one of
> those package deals at  Autozone, you know for about $0.43 you get 5
quarts
> of oil and a  filter.
>
> So, first, I took some oil out, it was near the high  mark (in the past I
> have suffered the oil pressure light on long  uphills, so I am familiar
with
> this problem).  The oil level is  now close to the minimum mark.  Problem
> remained.
>
>  So it was a Bosch filter, and in the archives this oil filter is
>  questionable.  So today I replaced it with a Napa Gold, which is really
a
> Wix, which was recommended, and the problem remains.
>
>  The oil is still golden in color and clear,no sign of chocolate mousse
or
> contamination.
>
> When I go downhill, at idle in  neutral, the light/buzzer go out after
about
> 7-10  seconds.
>
> The next step I am considering is to get some  different oil.  I know I am
> being a bad vanagon owner, but I  can't even recall what oil or weight I
> used, pretty sure it was 40W or  close to that.  Probably Castrol or
> Pennzoil, just can't  recall.  So I am thinking of putting some 20W-50 in.
> Am in San  Diego, really never drive it below 40 degrees, but this is not
a
> high  temp / high stress problem, we are in the 50s-60s each day.
>
> I  think I have a "frothing oil" problem of some type.  Another post  said
> that "Castrol GTX 20w-50 is only $13 for 5 quarts at Wally  World", maybe
not
> anymore, but I haven't been there is a  while.
>
> Any comments?  Thank you!
>
>  Roland
>
>
>
>