Link G4x Monsoon trigger input

Hi all,

I have just finished putting together a loom and standalone install on a bmw k1200rs engine fitted in a Hillman Imp. I’m having some grief getting it started, basic settings are all in there but I think my trigger scope readout looks odd. What would cause this, the trigger wheel and reluctor sensor are part of a kit, and all appear to be centred.

help please

Mike

First, do you have a good strong battery when cranking. Often we've discharged the battery while setting up the ECU, then we wonder why it struggles to crank with it only has 11.7 volts to start.

The trigger 1 (crank sensor) waveform is what you expect. When the engine is turning faster, the amplitude (height of the waves) is larger, and when the engine slows down (due to cylinder compression), the amplitude will be lower, and the space between waves will be larger. A similar thing can happen if the distance between the trigger wheel and the sensor changes. Remove the spark plugs and turn the engine over slowly and measure the the gap (using a feeler gauge) at different crank positions to be sure.

I don't know whether you expect a signal on trigger two, but right now there is basically nothing there on the phase of the engine you captured, you want to zoom out until you see at least three of the missing teeth (the funny twice a wide wave, with the diagonal rising edge) that you have one of at each end of that picture. If during the next / previous crank cycle, there was a triggerable event on trigger 2, then you would have the necessary bits to know the engine timing.