Let me just take a guess here. I bet you don't have the
original sheild on your O2 sensor, that was installed from the factory?

            Eric                   86-VW4x4
            vw4x4@fyi.net          72-240z
            Pittsburgh, PA USA     1936-Chrysler

On Thu, 28 Jan 1999, Nathaniel Merrill wrote:

> If any of you read my last post on Digitool readings and oxy sensors a few days ago you would have noticed that the conclusion was that the oxy sensor I had was shorting internally and Voltage from the heater was corrupting the signal to the ECU.  I was reading several volts at the Ecu (through the Digitool) on several occasions.  This was a intermittent problem which disabled the van- USUALLY associated with rain (and I live in Seattle).  I replaced the sensor yesterday with the "F**D" connector oxy sensor (U.S.  part # 13913).  Van runs great and all readings are normal.
> So I decided to look into the old one to see what I could find.  I ripped the "top" off the sensor where the wires exit and found WATER inside the metal cap and the rubber plug--- around the connectors for the three wires.  Also It looks like there may have been water in the main body of the sensor.
> So now I am wondering if there may be differences between oxy sensors?  Is it possible that some sensors are more suitable for exposed mounting like on the vanagon?  The old sensor I opened was also a 13913 F**D sensor with only 10-11K on it.  Anyway I intend to seal my new one well with oxy sensor safe rtv silicone.!
> Nat
> Seattle
>