[dcb]

FYI, I moved my tap to the injector lead itself. What I thought should be an injector lead on the ecu wasn't panning out?!?

Also, I'm not convinced this input circuit is doing anything. I don't have an oscilloscope unfortunately, but I probed around with a piezo and could hear the injector signal with it connected to the injector lead, and also could hear it across the 100k resistor, but cannot hear any ticks getting to pins 2 or 3, with the other end of the piezo grounded, or hooked to positive. Will try again on the breadboard version. Might need more thinkin, I will probably try just a 100k and some zeners next.

So I'm at a loss to explain the first trips readings...