The recommended service is 90,000 miles. My experience is that 50-60 is the
usual for many cars. Replacements are all over the place with probably a
10-20% short term failure rate. Sensors can also fail from contamination,
both internal and yes, external. They work by sensing O2 difference between
the exhaust and the outside air. The rear tire throwing all that crap
towards the sensor is a bad thing. Also, it needs to get hot and stay hot.
Do you have the heat shield or wind deflector. Most Vanagons are missing
this piece. Often the sensor is replaced and the new may overcome other
wiring problems that were really causing the grief. You should do some
testing before just replacing the sensor.

Dennis

>From: Tom Forhan <fourwdvw@YAHOO.COM>
>Reply-To: Tom Forhan <fourwdvw@YAHOO.COM>
>To: vanagon@GERRY.VANAGON.COM
>Subject: 02 Sensor expected life?
>Date: Sat, 17 Mar 2007 06:20:55 -0700
>
>About two and a half years ago I replaced the 02
>sensor after getting the classic symptoms: sudden no
>power condition once warm, correcting itself for a bit
>when ignition switch was turned off to reset the
>computer to thinking it was in cold start mode.
>
>It ran perfectly for trips to Maine and WV after I
>replaced the sensor, bu admittedly the total miles are
>since the replacement are low - about four thousand.
>The vehicle is not, obviously, a daily driver.
>
>Now its doing the exact same thing again. Stalling out
>about a mile from my house from a cold start,
>responding to ignition key resets. Could the 02 sensor
>have failed again?
>
>Thanks
>
>Tom F.
>90 syncro westie
>
>
>
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