Finally got around to replacing my '88's O2 sensor.  I was dreading it
because of the general condition of the exhaust system, very rusty.  I
tried the penetrating oil, a torch, hammer whacks, eventually committing
myself to destructive removal by removing the wiring etc. from the
existing sensor and using a 22mm 6-point on it, which worked.  I have a
proper O2 sensor socket, but it can and does flex open like a line
wrench when used on a very stuck sensor because of the large slot on the
side for the sensor wire.

Anyway the 6-point worked and I cleaned the threads with a spark plug
thread cleaner, and installed the new sensor.  The new heated sensor was
a plug-in (except with some extra harness) from a local chain store for
a good price.  The old sensor was black and sooty, so I'm glad I swapped
it.  Usually when they're in good shape they look more like a spark plug
from an in-tune motor, tan dry and clean.

Looking forward to improved mileage!

Gregory Smith
'88 Vanagon GL

Smith Design Studio
Small Building Company
Olympia, WA
360-239-0429
gregoryfsmith.com