So, I tried turning the van off and on again quickly. The symptoms you
described below of things resuming normally and then messing up again soon
after were exactly what I experienced. I checked the 3 wires coming from
the new O2 sensor. The single wire had a little corrosion on it, so I
cleaned that up and the AC semed to work fine for a few days, then returned
to the same symptoms.

Rechecked that connection again and cleaned it a little more (still in good
shape), but didn't make a difference. Fore good measure, I cleaned the
contacts of both ends of the trans-chasis ground strap (since it was on my
to-do list anyway), but still no luck.

I think it would be highly unlikely that I have a bad O2 sensor since it's
new. What I could see that would be more likely is a leak int he exhaust
pipes before the 02 sensor or I've gummed up the O2 sensor from running too
lean at times. Thoughts? (as I dig out the Bentley to start chasing down
the O2 circuit for bad conections or opens).

Gregg
90 Westy (Blueberry) - in hot VA weather

On Fri, May 18, 2012 at 9:01 AM, Gregg Carlen <gregg.carlen@gmail.com>wrote:

> Thanks guys. I'll definatly try that this weekend. A quick visual
> inpsection didn't reviel anything obvious. In having the engine work done,
> I had the mechanics install a new O2 sensor, so that would align from a
> timeline perspective of when the symptoms started. I'll let you know how it
> goes.
>
>
> On Fri, May 18, 2012 at 8:52 AM, Ken Wilford <kenwilfy@comcast.net> wrote:
>
>> Gregg, as Dennis says, when the van is running poorly, try turning the
>> ignition off and then back on again.  If the van runs better for a minute
>> then starts messing up again it is definitely an oxygen sensor problem or
>> an oxygen sensor circuit problem.  Let us know what you find out.
>>
>