I don't think it is possible to reprogram the Digijet ECU.  Only the
late Digifant models that had D at the end of the part number were
"chippable" or to some degree capable of reprogramming.  How much I
don't know.

These are very primitive Fuel Injection systems compared to today's
vehicles.

For example, I have a tuner for my Zetec in the Syncro all the time and
can switch between a stock tune and three Custom tunes in less than 2
minutes simply by stopping, plugging in the tuner to the OBDII port and
pushing a few buttons and then restarting and driving off.  It is
possible to customize the tune file on a PC (if I knew how - Bostig does
it now) and transfer new tunes to the tuner by connecting it to a PC
with a USB cable.

And, I  can use the PC to monitor dozens of engine functions in real
time, log the data for later review, creation of charts and graphs,
etc.  Another advantage of converting to an OBDII engine for the Vanagon.

Back to the Digijet:

A properly adjusted FI system with good wiring and a good O2 sensor
don't have any significant problems.  Most of what it sounds like you
are trying to fix isn't a problem with a Digijet that is running
properly.  I've got over 220k miles of Digijet driving behind me and
haven't experienced these problems.  Now I have had other FI related
problems, but not these O2 sensor ones.

Seems like it would be easier to fix the existing system and install the
heat shield that was there in the first place.

If you do try to use a heated O2 sensor, the black box on the back left
of the firewall should give you a switched source of 12V power IIRC or
the wiring that goes to the fuel pump relay box should have one.  I am
not the best wiring info source, but from doing diagnosis on my balky
starter, I think I remember there are switch sources in one or both of
these places.

Sam

--
Sam Walters
Baltimore, MD

89 Syncro GL, Zetec Inside
85 Westy Weekender
85 Mercedes Benz 300D Turbodiesel - to become veggie oil powered

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