Volkswagen United States, Inc. recommends the use of gasolines which
contain detergents to keep intake valves and fuel injectors free of deposits.

Gasolines without detergents tend to clog fuel injectors and leave
residue on intake valves which can cause unstable idle, surging,
misfiring of sparkplugs, stlling and rough engine performance in
vehicles with fuel injection systems.

Because many of our customers may not know whether or not a particular
brand of gasoline contains these detergents, we have examined
advertising literature published by gasoline refiners and other publicly
available literature discussing gasoline ingredients.

We cannot independently confirm the accuracy of gasoline advertising
claims.  The brands of gasolines listed below are claimed by their
manufacturers to contain detergent packages designed to keep intake
valves and fuel injectors clean.  There may be other manufacturers that
offer similar detergent packages.

Please pass this information on to customers who have experienced
driveability problems that may be caused by carbon deposits on intake
valves or fuel injectors.

   Amoco:                  All grades
   Arco:                   All grades
   Chevron:                All grades
   Citgo:                  Some grades in early 1990
   Conoco:                 Some grades in early 1990
   Diamond Shamrock:       Premium grade only
   Exxon:                  All grades
   Fina:                   All grades in early 1990
   Hess:                   All grades in early 1990
   Marathon:               All grades
   Mobil:                  All grades
   Phillips 66:            All grades in early 1990
   Shell:                  All grades
   Sunoco:                 Premium grade only
   Texaco:                 All grades
   Unocal:                 All grades
   Hess:                   All grades in early 1990
   Hess:                   All grades in early 1990
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Joel's note:
   i went though this with my 1986 vanagon and with my 1988 vanagon. in my
   particular case and in my particular region of the country, this was a
   waste of money and time. i had the $60 deposit removal procedure done
   three times, used about a case of Autobahn Gasoline Additive, P/N: ZVW
   239 003, AND Chevron Techron, swapped brands of gasoline (i was told by
   the vw dealer here that ONLY Amoco could be run in my 1986 vanagon,
   because all the others had caused the deposits that were causing my
   problems!).  all of that had NO effect on the idling and stalling problem.

   when i changed the coolant temp sensor, the problem went away. it came
   back again, changed the coolant temp sensor again, and the problem went
   away again. go figure.

   as far as brands of gasolines are concerned, we have three (3) suppliers
   in this town and it is NOT unusual at all to see a Parade gas truck
   unloading fuel into an Exxon station's tanks, or an Amoco truck unloading
   at a Unocal station.  so how do you know what 'brand' of gasoline you're
   getting??
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