OK, bear with me, but I've spent the past hour searching the archives and to
not much avail...

Patient:  1987 Vanagon Syncro

Symptoms:
Two, which may not be related.

(1) after running for a few minutes (i.e. not stone cold, but not full operating)
the van stumbles on acceleration - does this for about 10 seconds (i.e. just
enough for you to panic as you are trying to turn across traffic), then "catches"
and  accelerates again.  This makes me guess Temp II problem.  Doesn't do it
every time.  Only every now and then.

(2) yesterday, while on our first long trip in it out to the mountains to go
snowshoeing, after driving on the highway for about 45 minutes or an
hour, it would cut in and out for a bit.  Now, before everyone begins screaming
"Vanagon syndrome!!!", it has the factory AFM harness, and
stopping and shutting the van off to reset the ECU did not help.  After going
snowshoeing and heading home again - same thing - van was good for 45 minutes
or an hour, then began hesitating again.  Now, the hesitating isn't crippling,
just momentary.  It almost felt like a little water in the gas.  But why would
it take 45 minutes to kick in, then go away again (would it get stirred up)?
 Everything here was frozen solid yesterday, so it's not the "wet short in O2
sensor" problem.

Not sure if (1) and (2) are related or not.  I can't really comment on how the
gas mileage is either, because I haven't driven the van regularly enough to
get a running average or anything (I noted that loss of fuel mileage can be
a symptom of certain things).  Yeah, and I'm gonna throw some water remover
in the tank, just for fun ;-)

So,  my search through the archives led to so many possibilities, that's why
I'm back here asking for help!  There are various fixes, from the cheap to the
ludicrously expensive!  Fixes ranged from fuel filter (with the Syncro's plastic
tank, I don't see rust being a huge problem), Temp II sensor, fuel pressure
regulator, AFM, ECU, blow the van up and buy a Toyota - ACK!  I don't mind replacing
the Temp II sensor and fuel filter, as they are cheap and easy to do (and in
all honesty, the fuel filter probably needs to be done anyways).

Sorry for dredging up an old problem, but everyone in the archives seemed to
have different symptoms than my patient.
Keith Adams
Calgary, AB, CA || http://www.clubveedub.com
86 Westy "Roxy" || 87 Syncro "Hugh"