MicroSquirt.com read only forum (Jan.15,2018)

I thought this discussion might have come up at one point, but not sure if a conclusion had arrived.

In my opinion, Sequencer should always be in wasted mode when RPM < cranking threshold. Including if it coughs a moment > threshold and continues cranking, should be wasted. The reason is that it will create a consistency with startup. Right now car will swap from wasted to seq even if motor never fires up.

Typically, car fires up right away, so it fires while still in wasted mode so that is how startup will be tuned.

In the event the car has fouled plugs, bad gas, or other mechanicals that cause hard starting.... the fuel will be wasted for first 8 signals, then it will change to sequential for continued efforts which can be totally different for various reasons (including subject to opening time settings, squirt timing - open or closed valves).

Any thoughts? Perhaps it can be an option, but I'd like to see it always like that - less check boxes instead of more options.

I will give it some thought, but to me, the transition from wasted to sequential should be smooth regardless of being in cranking (simultaneous injection) or sequential. Once the sequencer is out and more people are running it, I would like to try some different starting algorithms. I know we had a problem transitioning to sequential, and I know I couldn't easily fix it, but it seemed like it would only affect one or two cylinder events and shouldn't be a noticeable problem, but I will review this when I get a chance. I believe it would be very easy to do what you want, probably only add the cranking rpm condition to the 8 successive cam synchs, so that is a lot easier than fixing the real problem. I might give you test code to try if you have a reproducible problem that we can evaluate whether this solves it or just moves it further down.

In thinking about it a bit more, there is some logic in doing what you say as it would transition from simultaneous in cranking , to paired squirts right after cranking, then to single squirts in sequential. Might be a bit smoother.

An additional thought on this....

Isn't the cranking PW a notional value, not adjusted for number of squirts?

Such that if the cranking pw that works for good starts is 14ms in wasted, but you have a hard start occasion that takes more than 8 pulses and changes to sequential... will the pulse width stay the same, but occur only once per cycle rather than twice?

Cranking overrides switching from wasted to sequential because in cranking you have simultaneous pulses on all injectors regardless of whether wasted or sequntial. In the sequencer you have 3 modes, but I am talking about the simultaneous mode. When not in simultaneous mode, the code accounts for the change from wasted to sequential by halving the fuel.