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Fluctuations in injector duty cycle

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hi everyone,

i tuned a nissan tb48 turbo charged car on motec m150, can is running staged injection, 6 injectors supplying pump gas and 6 methanol.

the issue i faced is that the methanol inj duty cycle is unstable and this increases as i increase the secondary contribution of the injectors. Also the same happens to pump gas injectors( primary) when i run only the primary injectors. What could be the issue?

log file is attached.

Attached Files

A screenshot of a log is not very useful, it would be better to attache the actual log. However, if I were to make a guess I would say it looks like it is just trying to compensate for your unstable "alternative fuel pressure". Where fuel pressure drops it bumps up inj PW.

The duty cycle isn't important (as long as you aren't maxed out at more than 85-90% ), what really matters is the Fuel Volume. As Adam has pointed out, the injectors will be open longer (larger duty cycle) if the fuel pressure drops. The amount is determined by your injector characterization tables, which depends on battery voltage and fuel pressure. I doubt you had the injectors characterized on methanol, so you may have more mixture fluctuation as the fuel pressure changes.

I think your primary focus should be to fix your fuel flow/pressure problem!

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