First I stand corrected I was mistaken there was a MAP which I found but
have not determined if I need to replaced yet.  Today I brought the van
to a friends shop and he tried to convince me that the timing belt was
off one tooth on the crank.  I torn it down enough to convince myself
that it was not off.  He stated that the idle vacuum at 15 pounds was to
low and that it needed to be around 20 pounds and that the timing belt
being off one tooth would do that. If it was consistently running rough
I might buy into it but it has a very unpredictable roughness to it.  I
adjusted the timing and took it for a short drive this evening and it
wasn't running to bad until I turned back into the driveway and then it
started to run real rough with the check engine light coming on and off
as the speed went low which relates too low vacuum which at a slow idle
I would expect.

I have checked and replace all the vacuum hoses that I though even
looked like they might be  a problem and so far have not seen any
improvement. I also sucked on the end of the hoses and have not found
any  that would not create a vacuum.  I am now wondering if there is
something going on with or around the fuel pump that might be causing
it. I kind of believe that fuel pump problems were hight speed related
but maybe not.

I did a test of pulling off spark plug wires one at a time and it almost
seems like number one cylinder isn't contributing much. All the others
slow down the engine until I replace the spark plug wire but number one
doesn't seem to do much.  Could this be an injector problem or a valve
problem from a valve not seating good enough?  I have ruled out the
spark plug which I have changed out without any improvement.

Answers ??
Thanks,
Ron