One thing I've been curious of:

Is an older ISV from other VW (mk II 1.8 Digifant?)
rated for same voltage and current draw range?
If so, if needed, I bet hose routing could be addressed.
OTOH, used 2.1 ISV's can be found. (thesamba.com)

FWIW, I've been running my '88 with the idle stabilization system
disconnected and holes at intake boot
and plenum plugged. Bus runs fine but needs to be warmed up on colder days.
However. I only have PS, no AC.

Neil.

On Thu, Oct 1, 2015 at 1:45 PM, Pat Spragge/RFAN <Pat.Spragge@rfan.com>
wrote:

> I'll need to track that wire and see where it comes from...since I have an
> early '89, it could come from either relay.  I've checked the voltage at
> the ISV connector with the ignition on  but not running and got 5V...which
> suggests that the ISCU is getting power from the ECU power relay and not
> the fuel pump relay....I think
>