I can't help you, but I can relate, as I too am experiencing what you have
described in my 84 westy (110 000 miles).  My gas mileage is very poor. I
commute 80km one way to work, the round trip is using approx. 25 dollars in
high octane gas, in the not to distant past this trip cost $10-15 . There is
a noticeable surging, with the peddle to the metal(as they say) I can feel
the van loosing speed on any incline, more than normal, but occasionally it
surges forward as if someone pulled up an anchor. I have leaking head
gaskets on both sides and I suspect the AFM is not functioning perfectly, as
I have intermittent bucking, hesitation, also I know the 02 sensor is
faulty.  Any suggestions, other than the obvious engine conversion.  This
started well after the o2 was known bad.

-----Original Message-----
From: Charles A. Strott [mailto:chastro@BOX-C.NIH.GOV]
Sent: Thursday, December 02, 1999 12:29 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Help

  I have a 1985 Vanagon camper with 130,000 miles and no previous
serious problems with the power train. Recently, the van has been
experiencing periods where it loses power but does not stall. When
attempting to accelerate, it feels as if the gas is being choked off,
yet if put in neutral the motor can be easily reved up. When
reengaged, however, there is no power and the car will not accelerate
(the van does not stall). If on level or going down hill, the car
will move slowly, but if going up a grade, there is little movement.
Appears to always occur from a cold start. Can occur when the gas
tank is near empty or full (usually use Exxon regular; however,
currently using Exxon high test, which has not helped). What is
frustrating is that the problem is intermittent. The car will run
>perfectly for a few days and then the problem recurs. Since the car
is presently used mostly for traveling to and from work (~5 miles), I
don't know if the problem will arise after extended driving.
Naturally, when I take the car to a garage for a diagnosis, the
problem wont occur for them. Also, during this period the gas mileage
has noticeably worsened. Would appreciate any help on this. Thanks.

Charlie
Charles A. Strott, M.D.
Section on Steroid Regulation
Bldg 49, Rm 6A36
National Institutes of Health
Bethesda, MD 20892-4510

Tele: 301-496-3025
Fax:  301-496-7435
e-mail:chastro@box-c.nih.gov