Cranking and ASE tuning
 

I am not understanding the cranking pulse theory. I have taken a ridiculous amount of fuel out, and I still open the throttle to start. Do I start at zero?

When ASE blips on ultra-momentarily during cranking over 300rpm, does it flip to that map?

Start attempts: 1, 2, third using throttle.

https://www.miataturbo.net/attachmen...ine=1351694506

https://www.miataturbo.net/attachmen...ine=1351694506

https://www.miataturbo.net/attachmen...ine=1351694506https://www.miataturbo.net/attachmen...ine=1351039814

https://www.miataturbo.net/attachmen...ine=1351039814
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most recent drop to 30% cranking did not save to msq, but it and log are attached.

The engine uses the cranking pulse width below the cranking RPM setting (which defaults to 300, but you can move it if the engine blips above that when cranking) and above that RPM will transition to the main VE table multiplied by the total of the WUE and AE values.

That is important information. I understood that the cranking RPM was when the table switched to run, but I hadn't thought that it would switch the fuel abruptly. Should the cranking rpm be adjusted to the max rpm seen while just cranking?

Does this mean adding a row below 1000 is necessary to help transition to running? This area will never get VEAL, so it would require manually inputting values between cranking PW and VE?

Thanks for responding Matt.


I raised cranking rpm to 550 and it seemed to change things.

Nice comfortable temperature this afternoon so I dropped cranking down to 20% and worked my way up to 60% where it started without throttle. Still not a perfect start, but better.

I see differences between logs, but still not sure what is changing what.



60%
Attachment 185726



55%
Attachment 185727



20%
Attachment 185728



Req fuel=11.9
Stock 1999 injectors

https://www.miataturbo.net/attachmen...ine=1351128816

Cranking rpm needs to be set just above the max that ever occurs while cranking, but not so high that your idle rpm could dip below it. Mine is set to 400.

You're asking about the VE table? Yes. The limits of the VE table should encompass all running conditions. My lowest rpm column is 500 and highest is 7500 (7200 rpm limit). But I still don't use VEAL to tune the idle region, I do that manually.

OP, where are you getting your cranking pulse values? The values in the DIY base map are a good place to start. Mine are tweaked only slightly from those and nowhere in my cranking table is there a value less than 100%. After you turn the key it shouldn't take any longer than whir-whir-whir-start. Should not need any throttle, and if you step on the pedal too much (I think the default is 70% TPS) it will go into flood clear mode (no fuel injected).
https://www.miataturbo.net/attachmen...ine=1351134551

Original values brain gave me look similar to yours.

With that much fuel, I had to crank first, then crank with flood clear mode engaged for it to catch and start. That, plus many cranking threads referring to starting 'low' ended me with the bonehead numbers above.

Past few weeks I had been cranking at 50% and still having to slightly crack the throttle, maybe 10%, to start.

Should I read more on idle air valve?

Just went back to normal settings, using ScottFW's above.

What to do? Is this sync loss something to be concerned with?


Attachment 185719
Attachment 185720
Attachment 185721
Attachment 185722
Attachment 185723

Started crapily this afternoon, now I can't get it to start. Wtf

It has officially been an hour of cranking.

I am wanting to pull a techsalvager on my MS

please have a look at the log and MSQ. I have another log that is over the upload size limit.


Here is something I thought of while driving home in a borrowed car: I made changes to the VE table in the upper RPM range since I planned to autotune. I do not believe that I ever power-cycled the MS. Could have been my problem??


I tried varying the cranking value to no avail. I even tried starter spray.

:crx:

You will never start with sync loss 32. Look it up.

Change your settings from falling edge to rising edge, or the other way around. I bet it starts right up.

Crap. And thanks, I will start reading.


Paging Braineak:
I remember us changing something about the rising/falling stuff earlier this year while trouble shooting something else. I'll look through the emails. :brain:

Brain, am I allowed to change the rising/falling edge setting? Any other thoughts?
Check out 3rdcar's thread: https://www.miataturbo.net/megasquir...ranking-67806/

I see both sych losses going back to logs when I first got the car running on MS. This must be the reason why I have been having issues cranking.

Does not synch loss after start. Only while cranking.

31 = Miata 99-00 - 2 cams not seen
32 = Miata 99-00 - 0 cams seen

Seems like the only threads where moving the sensor closer is necessary is when the synch losses occur while driving. Seen a few threads where it is purely software settings. Promising...

To get the sync loss resolved, could you get a composite log of an attempted start, and attach the whole file to a post?

This will help a lot. Please do the above (screen shot it if you can right now, I cant open a composite log here)

But please refresh my memory: You have an Ms2 w/harness for your '99, right, and not a black DIYPNP box?

If so I built the AbeFM inputs, so you need Falling Edge, not Rising. The map you posted appears to be on rising.

Looking at your logs I can tell it's the sync loss that's causing all the havoc.

Thanks Matt and brain.

I do not have a recent composite log. Next time I will be around the car is the 10th. I will flip from rising to falling edge and log all the things.

Correct, I have a ms2 with harness for my 99, and not a black diypnp box.

okay, i believe that's the issue then. Report back, Private.