Hello,
      I have an 85 Vanagon Camper which experienced low oil pressure
around idle and loud valve noise.  The power would diminish as the
engine warmed up. Eventually, after 10 minutes or so 2000 rpm was
difficult to achive and was combined with very loud engine noise and
detonation(as I interpret the noise).
      After having a seemingly competent VW specialist spend several
days analyzing the problems and making sure the valves and timing are
adjusted properly, I've been told that the lifters on one cylinder are
not holding the valves in adjustment(this cylinder initially had very
low compression). The mechanic says to determine anything more, the
engine must be disassembled.  A preliminary hypothesis is that the large
end rod bearing are worn and caused the low oil pressure which in turn
caused the problems with the lifters and valves.
      The engine had 146k miles with new heads at 100k.  Does anyone
have an opinion on this or as experienced anything similar?  The van was
driven around the country last summer, then left fairly undriven during
Oct.-Feb.(maybe driven 150 mi.).  The problem occured quite suddenly, no
slow derioration so I am wondering weather a worn out bearing would
really show itself this way.  Any ideas/help/suggestions greatly
appreciated.

  James