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Cossi Triggerpage

Engine starts only with reverse crank sensor polarity.

reverse of the factory?
or reverse compared to what should be good ?
- reverse of the right polarity, VR sensor signal is rising. ( in this case I won around 10 degree of advance)

Primary tigger:

Secondary trigger:

817 Ohm (with sensor disconnected)
0 mV (with sensor connected, ignition ON, not cranking)
- NO pullup: might be very sensitive during cranking. 10..22kOhm pullup to +5V might help
  - Tried, but nothing changed. The same result with 10-15-20kOhm pullup to +5V. We get good rpm values, but so far I can't adjust TDC with the ign_tdcdelay value.

The LCD and Megatune shows the right RPM during cranking.

When I try to positioning ign_tdcdelay, I get only erratic crank angle (measured by strobe) as I change the value:

(ign_crank_advance=01 ,crank advance 0.25 degree)

It's looks OK, but if I use the right crank advance (8 degree through the crank),then get spark BTDC 70 degree again.

I can't make spark between BTDC 70 degree and ATDC 2 degree.

2007-08-13

I do some measurement by scope with 15kOhm pullup to +5V on secondary trigger (both sensor conected with the right polarity) :

Cranking around 210-220 rpm

CH1 - cam signal

CH2 - crank signal

These are looks good for me, but I'm not sure of course, because the problem with the spark advance is still the same.