Thinking back to basics here.Dookie454 wrote:I scope high and low opti signals, with and without spark... All ok. No difference.
Scope of low res and tach/coil output looks fine without spark powered up... Once spark is on, the low res is fine, but tach/coil drops out, kinda jumps all over when sync loss.
The firmware doesn't know if you have a coil connected or not. The output is just the same and there is no monitoring.
So, it seems, the only way that hooking up the coil can be causing a problem is interference with the signals getting to the Megasquirt (or even inside the Megasquirt.)
I'll see if I can think of a way of making the sync-loss reporting more informative so we can track down exactly what the firmware doesn't like about the input signal.
James