The AFM is my best guess!!!  Or a leak in the air intake system.

Having owned both a 1.9L and 2.1L (same 84 Westy), the AFM issues seem to have the same impact leading to the "flat spot" when accelerating.

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Loren Busch
Sent: Wednesday, May 05, 2010 11:39 AM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: 84 Westy stumbles off idle

 RE: Flat spot when accelerating from a stop with warm engine
I'm following this thread with a lot of attention since I've been dealing
with/just dealt with the identical problem with the 2.1L in my '90.
Had been running fine for several years.  Last December, just before a long
trip and while having a bunch of other routine maintenance done I asked my
mechanic to check the timing, not looked at for a long time.  He checked it
and tweaked it, said it was just a little off spec.  But driving away from
the shop I found that full throttle acceleration from a stop, after warm up,
was flat.  Didn't stall or die, just flat until about 2,000 RPM.  Lived with
it for the trip.  And one of the most knowledgeable Vanagon people I know
checked everything out when I stopped by his place during the trip and
couldn't find anything.  When I got home I got together with my mechanic
again and we tackeled the problem.  Ended up advancing the timing to about
10 degrees and that cured it about 90%.  But could find nothing else. Whats
been said here leads me to want to try the spare (and virtually new) AFM I
have.  The current AFM developed 'Vanagon Syndrome' about a year ago (cured
with the factory pig tail) so I'm wondering if the problem lies there.  BTW,
155,000 on the van and still the original engine.  Gas mileage is where I
expect it, 18-19 on the highway, and runs great otherwise.
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