In a message dated 8/12/99 8:14:21 AM Pacific Daylight Time,
webbd@HOFFMAN.ARMY.MIL writes:

<< I've suddenly been having a problem with my 93 Eurovan, and my VW dealer so
 far hasn't been able to help me.  So I was hoping someone on this list may
 recognize ths problem, since the symptoms are very distinctive.

 My 93 Eurovan (45k miles) has always been very reliable.  But on a recent
 long trip it began dying on the highway without warning.  The circumstances
 are always the same: after an hour or more of constant-speed highway driving
 it will suddenly and without warning lose all power, so I have to coast to a
 stop on the highway shoulder.  The engine does not stall out.  If I turn it
 off for a few minutes and start it back up, I have always been able to drive
 away okay without further problem.

 This is apparently a known problem with some non-Eurovan VWs (including
 Vanagons), as I have found a description of it online, as well as a standard
 fix.  Here is the fix that is prescribed:

         " Some VW cars have a mass air flow sensor that
      vibrates the potentiometer arm during extended driving
      at constant speeds. The resonance causes the mass air
      flow sensor to send an intermittent signal to the ECU. The
      ECU will default to a no load signal and reduce injector
      open time. To remedy this problem install a
      damper/converter (p/n 025-906-302A) between the wiring
      harness and the mass air flow sensor connector."

                 (from Automotive Machine & Supply, Inc website)

 My VW dealer says he is familiar with this problem and the fix, but has not
 yet seen it in a Eurovan (except mine).  So he is trying to get VW to
 investigate and come up with a fix.  But it's been a while and VW so far has
 nothing to offer in the way of a solution.

 Has anyone on this list had this problem with sudden power loss at constant
 highway driving?  Does VW have a Eurovan fix for this comparable to the fix
 for their other cars?

 Thanks very much for any help with this.

 --Dennis Webb
         '93 Eurovan
         '77 Microbus
         '70 Green Beetle
         '67 Red Beetle

  >>
The fix is simple. You need a new power supply relay. It is located in relay
position #3 up in the fuze box. If you open up the relay, and with a
magnifying glass look at the circuit board, you'll see a bad solder with a
crack around it. When it gets hot after the car has been used for a while,
the solder expanse and breaks contact. The car dies but restarts shortly
later when the relay has cooled down. This has been an ongoing problem on
early VW's using this relay, around 90 -95 models.
 If that doesn't fix the car, you need a new distributor. VW scan tool 1551
will not pick up a fault on 93 Eurovans if the distributor is bad. The fault
stored if the engine computer was designed to read and store distributor
faults would say "Camshaft position sensor fault, sporadic" You can unplug
the distributor while the engine is running and the computer won't store a
fault,, too bad. Makes my job harder when diagnosing these problems.
 I'm shocked that your dealer doesn't know what to look for. There's even a
tech bulletin on those relays. See ya, a fellow VW dealer Tech. Michael.
 87 syncro
 87 quattro