I agree, since all I did for placement was get it near the engine, but now that I have a few more facts, 1.6 volts is enough to drive an LED, how many uamps will that take...., or maybe a hall device and since all the electret mike did was create a wave form, maybe I can make a better wave form. The bottom of the engine is easy to get to, so if i make a white spot on the belt drive on the front of the engine ..... maybe tape a vane to it and place the mike close to that, maybe put the mike in the air intake manifold, I like this idea, i wonder how much current is available.. It's early, I just got up, sorry for rambling, I let you know how putting in the intake works. I think the app on the phone was meant for something like rotor blades or exhaust pipe sounds,, maybe try a different mike
Jeff