Your "mechanic" needs to know that the injection is continuous, hence there is no injection timing.

There is a flywheel trigger pickup for the ignition, and that signal also controls the fuel pump relay when the engine is running (though not when cranking to start engine).

First tests:
Can you hear the fuel pumps run for about 2 seconds when you turn the key to "on" (not start)?
Is there spark at the plugs when cranking?