Mike
Try swapping out the coil.  I was chatting with my local VW specialist
about something similar and he suggested that maybe the coil was
failing as it heated up. It seems to be the only thing you haven't
checked/replaced in the ignition system.  Good luck
Don
On Tuesday, May 18, 2004, at 10:00  PM, Automatic digest processor
wrote:

> Date:    Tue, 18 May 2004 20:40:08 -0700
> From:    Michael Brenner <brenner9@YOSEMITE.NET>
> Subject: Re: Timing
>
> I think I may have a timing issue with my 84 Westy. When reading the
> Bently
> manual, I'm a little confused as to what RPM you set the timing at.
> From
> what I can  make out it appears to set the timing at 2500rmp? Is this
> correct? (I have had to set early 911's at 6000rmp, which was a lot of
> fun
> to stand behind with this screaming motor). Trying to diagnose a wierd
> problem. The van fires up and runs for about 3 to 5 minutes, and then
> gradually misses and stalls completely and will not start, not even
> with
> ether. When it cranks over it has that sound and feel like the timing
> is
> off, but never fires at all. I usually have to wait until completely
> cold
> before it will restart. I have tested the sensors, the air intake
> plate, the
> deacceleration switch and the full throttle enrichment switch, and
> they test
> good. Tested the hall unit for voltage and flicker, and it tested ok.
> The
> injectors have new seals and do not drip. New plugs, cap, rotor and
> wires
> (the correct wires). It seems like the timing drifts away, if that
> makes
> sense. As soon as I can adapt my american fuel pressure tester to the
> german
> test port, I will see what the fuel pressure is doing. Compression is
> ok,
> not great, 120-125 when the car is warm.
>
> Any suggestions would be greatl;y appreciated.
> Mike Brenner