I had a Bosch generic three wire O2 sensor go bad after it was a month
old.  The Bosch representative said it was the wrong generic three wire
sensor. Well I emailed the list with this bit of trivia, and heard back
that the Bus Depot $40 Bosch three wire sensor I purchased was
"functionally identical" to the Bosch $120 Cdn generic three wire
sensor.

My only guess is that the Bosch generic three wire sensor listed for the
Vanagon, incorporates some type of waterproofing or corrosion resistance
due to the sensor's placement on the vehicle.  My would only act up at
first during wet conditions.  I even had the little splash shield installed.

My advice is if you are in a area with a wet season, stay away from the
generic sensor that isn't listed as vanagon specific.

Sincerely,

Mark Keller
91 Carat
Cowichan Bay, B.C.