Sounds like you got a renegade AFM.
Run through the entire sequence of checking injectors for power (I use a
little neon bulb on a long wire), it works to check your cold start too.
Check all ground wires
Set your valves to one turn down from the rocker arm just touching the
valve stem.
------the idle screw has no effect. -------- Check your vacuum after you
do these things. Check vacuum at 800-900 rpm and 1600 RPM like the manual
specifies.
If these things check out you may need to remove the AFM cover and set
the tension on the flapper valve. Its not all that hard to do but you
need to try a known to be good AFM before you start setting the supposed
bad AFM.

Stan Wilder

On Sun, 30 Dec 2001 15:24:36 -0500 Adam Puzerewski <VGONMAN@MSN.COM>
writes:
> Volks,
> I am having a wierd problem.  As of late, the fuel consumption of my
> freshly rebuild engine is falling. i am getting 12.5 mpg..........
>
> I know my valves are at zero lash.........
>
> Here are the strange symptoms.  Crappy cold idle, sorta rough.
> around 400-700 rpm, and turning the idle screw has no effect.  Once
> it warms up, it holds 1000 rpm or so no prob.  These latest things
> happenned after I adjusted the valves to zero a month or so ago.
> Prior to that, no probs...........so, one would think well, adjust
> them back?   Well, I reply what is the reason?  They are at zero
> already and what could be the advantage to that.
>
> Prior to this latest valve adj, I had the CO set to 2 % drove about
> 1800 miles over thanksgiving, the whole while averaging about 16.5
> mpg.
>
> So, I go to type2.com ;library and go thru the fuel injection
> troubleshooting.
>
> Test pressure regulator, and it is in line.35 psi or so at idle, and
> when you give it throttle, drops to 30 or so.  In the ballpark for
> the crappy gauge i own.
>
> Checked resistance at the temp sensor on cylinder 3 and it was in
> line after warming up at 67 ohms.  I replaced the thermo-time
> switch, and same result.
>
> Looked at the injectors for leaks, and not
> happenning................left the fuel pressure gauge on for an
> hour and it stayed steady.
>
> Timing is set at 7.5 btdc at 1000 rpm..............spot
> on.............
>
> I am thinking MUST be auxillary air regulator..................any
> thoughts?
>
>
> Adam P
>
> 81 Vanagon westy ( The Brick)
> 70 SingleCab "Whitey"
> 74 Beetle "ol yeller"
> 73 Transporter (STILL at paint shop)
>
> Used Vanagon Parts for sale (mostly aircooled)
>
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