Well, the spark tester would have told you it was an ignition failure, but not why it was failing. You'd have disconnected the kill wire and found the problem was gone - then you'd have had to trace out the kill wire circuit to find where it was happening.
I think a low oil sensor is an important feature for a medium-sized generator like that: people use those in holiday shacks or camp sites and leave them running until they run out of fuel, then refill the tank without checking anything else.
Unfortunately the oil sensor will probably be one of the chonda bits that is not an exact copy of a Honda part, and it may turn out to be troublesome even after you fix it.
I'll close this thread.
