FYI... regarding Bosh Oxygen sensor - same as at our favorite vendors

http://www.autozone.com/engine-management/oxygen-sensor/bosch-oxygen-sensor/volkswagen/vanagon-2wd/1990/4-cylinders-b-2-1l-fi/232283_115960_1784/

On Thu, Oct 30, 2014 at 10:05 AM, Stuart MacMillan <stuartmacm@gmail.com>
wrote:

> Of course it works fine, the only reason for the heated version is to have
> lower emissions during cold start warm ups by getting the 02 sensor working
> quicker, which isn't even measured during state emissions tests.  It's an
> EPA requirement, and every little bit helps over millions of vehicles.
> There has been a long effort to do all kinds of things to warm engines up
> quickly to minimize cold running richness.  For example, my '06 Scion won't
> upshift to "drive" below 35 mph until it's been driven for about two
> minutes.  When I first got the car I asked the dealer if this was normal,
> and it is.
>
> Your idle drop issue after a hot run is not due to the O2 sensor. More
> diagnostic fun in store!
>
> Stuart
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf
> Of Don Hanson
> Sent: Thursday, October 30, 2014 9:35 AM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Single wire Oxygen sensor: Substitution report..
>
> I run digifant engine management for my inline VW ABA Jetta motored
> vanagon...same as the stock Vanagons but with the inline motor providing
> the go..A few weeks ago I had some problems with my engine management
> system and traced it to a dysfunctional Oxygen sensor.    I'm almost
> positive the problems were a result of bad wiring between the O2 sensor
> and the ECU, but I have no actual confirmation of that.
>
>    Anyhow, I was unhappy with the cost of replacing the Bosch 3-wire
> heated Oxygen sensor in my rig...the best I could find was about $70 for
> another Bosch heated sensor, and  that one didn't even have the proper plug
> for my wiring harness...So I did some research, called around a bit and
> asked...and the general response was that I could replace that 3 wire
> heated oxygen sensor with the single wire Bosch sensor and save myself
> about $50 without any real downside to engine performance.  But......No one
> would actually come right out and tell me that.   Lotta "Oh, that should be
> OKs"...and "I don't see any reason why that wouldn't work fine"s....There
> was also some nebulous opinion as to how to properly connect the
> sensor...Should the shielded wire loom carry a grounding connection or
> not...etc...
>
>    Anyhow I bought a single wire Bosch from Van Cafe and installed it.
> The results are quite satisfactory.   The only downside has been that after
> sustained highway driving if you shut off the motor for a short while the
> idle speed is a little low...low enough to stall sometimes...for just a
> couple of seconds, until the O2 sensor gathers enough heat to resume proper
> function, I guess.
>
>    I have regained my fuel economy...back up to 24.xx mpg after 3000 miles
> with the new sensor. the O2 sensor i again modulating the fuel mix
> properly....When running with the O2 sensor disconnected from the ECU, I
> was seeing around 4-6mpg less gas mileage but the motor felt quite happy
> and strong..
>
>    So, in my case, I successfully saved some money on that part and gained
> back my good gas mileage.   Here's a handy app to help you track your
> fuel...there's one for the smart phones, too....
> http://www.fuelly.com/dashboard
>