The simple answer is always "Don't do this." But we are fearless Vanagon pilots and mechanics, so off we go!

  There is no difference in the OUTPUT to the ECU between 3-wire and 1-wire Ox sensors. The 3-wire has a heating element built into it to allow the sensor to be "in range" sooner, and allow lower emissions. The ECU will ignore the input from the sensor while it is "out of range", especially at startup.

  So, the answer is that either sensor can be used on either engine, but there will be a price on the 2.1. It wants to see an "in range" reading much sooner, and may not like not getting that input.

  <snip>

Can a 3 wire 02 sensor be used on a 1.9 engine by running a 12 volts to
one of the white wires and grounding the other?

Perhaps the answer(s) to both will enhance understanding.

Mike

John Rodgers wrote:
> Can the one wire version be used on a 2.1L engine?
> If not, why not??
> If so, what is lost without the other two wires.
>
> My newly installed 3-wire O2 sensor apparently has an internal fault.
>
> I have a brand-new-in-the-box 1-wire O2 sensor.
>
> Thanks,
>
> John Rodgers
> 88 GL Driver
>

Evan Mac Donald

1984 Wolfburg
1985 GL 7 Pass.
1991 Carat Weekender
1972 Chevy P/U
1993 Bonneville