HI Marcus,

        This is a perfect question for this list.  

        Likely there are several things to check. 

Did you win one of the gift certificates from Vanagain?  That could help with parts.

So, 

I am the least qualified to answer, but why should that stop me?

Fuel filter clogged?
Water in tank from either bad ga or past water event in evaporation tank? 
Charcoal canister, is there suction when you take off the gas cap? 
Only happening when hot, would that be caused by something in the O2 sensor?

Could try to unplug the sensor just to see if still happens. 

And almost last, tune up with new wires. 
And lastly, of course, check all your grounds!

Got a friend with a 2.1 vanagon? Try his AFM.

Maybe when Denis gets home from WRW he can send some ideas.  He is likely driving his slightly large van home today.

Eric Caron 

> On Jul 15, 2024, at 1:43 PM, Richard Koerner <rjkinpb@SBCGLOBAL.NET> wrote:
> 
> How old is your fuel tank?  Clogged fuel tank outlet will start causing these issues.  Was it a hot day?  High ambient temperatures makes it easy for Fuel Pump to cavitate; these bubbles in liquid fuel cause loss of power and even dying.  Next day after fuel is cold again, the problem disappears.  But then you drive again on hot day, and problem reappears as gasoline in tank warms up to ambient.  Since fuel tank is downwind of radiator, all that hot air flowing by helps also to heat up gasoline.  If clogged outlet from old tank, there is no fix; you've got to replace Fuel Tank.  
> 
>    On Monday, July 15, 2024 at 10:03:09 AM PDT, Markus Benne <mbenne@m-bass.com> wrote:  
> 
> 
> Driving home from WRW, the car had several (usually about once an hour) hickup events during the 8 hour drive home.  Sudden momentary loss of power and then back to normal.
> The Bus is a 90 with original 2.1, so it already came from the factory with 025.906.302 which is the supposed fix for Vanagon Syndrome.  
> Is it possible that the little pigtail went bad?
> ...Markus