> PO (original new owner) told me the fuel lines were replaced
under a recall.
> Any idea what year(s) this may have been done?  Vehicle is a 90
multivan.  I
> have examined the lines and they have not concerned me---yet.

you can go to www.nhtsa.gov  and search their recall database ...
scroll down to Recalls,
then on that next page, click on Search by Make and Model,
then put in the info as needed and submit each time. this is what
i found for 1990 Vanagon, fuel system related:

      Make : VOLKSWAGEN Model : VANAGON Year : 1990
      NHTSA CAMPAIGN ID Number : 92V058000  Recall Date : APR 08,
1992
      Component: FUEL SYSTEM, GASOLINE:DELIVERY:HOSES,
LINES/PIPING, AND FITTINGS
      Potential Number Of Units Affected : 358000
      Summary:
       THE FUEL HOSE ATTACHED TO THE FUEL DISTRIBUTION RAIL ON
THE ENGINE MAY SHRINK BEYOND THE CLAMP FORCE OF THE FUEL HOSE
CLAMPS, ALLOWING FUEL TO LEAK.
      Consequence:
       FUEL LEAKAGE IN THE ENGINE COMPARTMENT CAN CAUSE AN
UNDERHOOD FIRE IF THE FUEL COMES IN CONTACT WITH A SOURCE OF
IGNITION.
      Remedy:
       REPLACE THE FUEL HOSE ATTACHED TO THE FUEL RAIL AND
INSTALL A NEW SPRING TYPE SELF-TIGHTENING CLAMP.
      Notes:
       SYSTEM: FUEL LINES. VEHICLE DESCRIPTION: PASSENGER CARS

      and this is some older material i had laying around on my
computer ...

      From National Highway Traffic Safety Administration
           Auto Safety Hotline  1-800-424-9393
      -----------------------------------------
           Information as of 06 May 1994
      -----------------------------------------
      1985 Vanagon through
      1991 Vanagon                Built from 1985 Jul  to  1992
Jun
           Campaign 92V058001     No. Recalled: 340,000
           Campaign SF            Notification Date:
           System:                Fuel Lines.
           Vehicle Description:   Passenger Cars.
           Description of Defect: The fuel hose attached to the
fuel
                                  distribution rail on the engine
may shrink
                                  beyond the clamp force of the
fuel hose
                                  clamps, allowing fuel to leak.
           Consequence of Defect: Fuel leakage in the engine
compartment can
                                  cause an underhood fire if the
fuel comes
                                  in contact with a source of
ignition.
           Corrective Action:     Replace the fuel hose attached
to the fuel
                                  rail and install a new spring
type self-
                                  tightening clamp.
                                  NOTE: Volkswagen of America
estimates the
                                  new self-tightening fuel hose
clamps will be
                                  available in May of 1992.
           Supplement 92V058001   Information has been added to
this campaign.
      -----------------------------------------

=================================================================
=======
      Vanagon, Vanagon Campers, Vanagon Syncros
      -----------------------------------------
      Volkswagen Recall Campaigns

        Affected    From VIN -            Date
      Year  Models  To   Vin             Issued   Code
Description
      -----------------------------------------------------------
------------

      1985 Vanagon                    -  1992/??  SV   Replace
clamps on
      1991 Vanagon  WV2**02**MH999999                  fuel
distribution rail
                                                       to prevent
leaks and
                                                       possible
fire.
      -------------------------------

      1990 Vanagon  WV2**02**LH000001 -  1994/03  RV   Replace
fuel injector
      1991 Vanagon  WV2**02**MH999999                  seals
(leaking)