This is true for early Digifant FI wiring harnesses like 86/87 but it
was changed in later years and the harness may have been updated by a
PO. The later year harness only powers the ISCU and ISV when the fuel
pump is on.

Mark

Germain wrote:
> Hi
>
> I am not an expert but chances are the ISCU could be bad. The ISV should be humming when the ignition key is ON without the engine running.
>
> You should try with a good ISCU.
>
>...............