First of all, thanks to everyone who wrote to me with suggestions on how
to deal with my loss of power/Vanagon stutter bucking problem on my 89
Wolfsburg that so many others have had.  I changed the temp sensor,
cleaned the air flow meter and put in the harness and my problems
continued.  I ordered a new oxygen sensor but thought I'd wait until the
problem reappeared to make sure I had the problem pinpointed.  Yesterday
I started losing power again and so immediately disconnected the O2
sensor and the problem went away for the remainder of the trip and since
I read that you could run disconnected without a problem I thought I'd
wait til I got home to put the new one in. When I started to drive home
I couldn't get any power and the van wouldn't go above about 40.  When I
stopped there was black smoke coming out.  After reconnecting the O2
sensor it ran fine again.  My question is, besides needing to replace
the sensor does this problem while it was disconnected indicate that
something else in the system is not operating properly?

Sorry this is getting long but there's one more question.  I don't think
this is related to the above but, when I began the trip home the battery
was dead (for some reason leaving the lights on for 10 hours completely
killed it) and I got a jump start.  Temperatures outside were mild and I
left the van idling for a long time scared to turn it off.  I noticed
that the fan came on and that the temperature was going really
high-almost halfway between the light and the top line.  I'm new to the
water-cooled world so this may be a stupid question, but, is it normal
for idling long periods of time to send the temperature so high? Thanks
for any and all help and suggestions.  It might be best to reply to me
at mschrope@vims.edu