OK so I would start by looking at your cranking pulse table and remove some fuel there.

It's had to say exactly how much without trying the car myself. Just keep in mind that too much fuel and too little fuel can both lead to flooding--too much is obvious, but too little wont burn and just makes a wet mess too.

I would start by aiming for 100% at normal operating temp and then dial it up or down from there. My last map was around 80% at 140F. Remember it's % of "Required Fuel".

And Required Fuel is the value calculated to roughly equate to 100% VE at 100kPa. And cranking happens around 100kPa. So it makes sense that 100% cranking pulse is going to get you about 14.7 AFR (ignoring the effects of RPM and airflow parameters of the engine). In reality, VE is pretty crappy at low RPM so you can tune for less than 100% and still be richer than stoich. If you can truly measure (i.e. your A/F gauge doesn't shut off) during cranking, you can try for 11.5ish AFR and see how it works. I don't remember the ideal value for starting but it's usually a bit richer because of cold engine parts and condensation.

Thank you very much ! :)

Don't know if I mentioned that I also get an occasional back fire from the exhaust as it starts …

This isn't going to be easy but at least I got trusted lap top back...

I did a "compare" between the tune that came with the MS3 courtesy of Brain and what my friend ended up with

These are the cranking/duty cycle numbers compare.

Coolant Duty (Base)
29 49
78 45.9
131.2 42.7
192.0 38

Coolant Duty (Current Tune )
0 60.0
60 40
120 36.1
200 30.2

Right now since I'm not the best at this stuff I'm tempted to try Brain's settings to see if the issue goes away without having to reinvent the wheel.

Changing starters sucks :hsugh:

Can somebody verify this ?

I played back the log of the motor cranking and spark timing shoots up to 25.4 degrees !!!

Wouldn't that cause those hard cranking episodes ? :vash:

is that what your cranking advance is set to? (this is under ignition settings)

my map comes with 15 or 18° IIRC.

Thanks !

I checked and it is set to 10 ?!

cranking advance, or do you still have fixed timing set to 10?

Yes, my cranking advance is set to 10 degrees.

Fixed timing is set to 10 according to the guy I gave the car to to wire it for sequential etc.

Should I check it ?

Thanks man !

Why is fixed timing active?

it shouldn't be, unless you wanna melt stuff. Which is exactly what I told you to check in your last thread about the heat from the trubo...

if it's set, then how are you seeing 25° during cranking?



you know what could help?









and i know this is crazy...








...to ask this in a megasquirt thread...










...where someone needs help with configuration and tuning...







































...but why not post the datalog of cranking and your MSQ so we can actually review it?






















I know, I know. that's a lot to ask for.

My bad.
I thought you meant the initial timing - the one you set with the timing light so that the timing on the tables is actually what it reads.

I honestly don't know where the setting you mention is ..

The MSQ and cranking logs are at the start of the this thread

Ok here is a log where the starter actually flaked out.
It cranked a few times and basically stalled and stopped cranking the motor over while I was still holding the key in the crank position.
I'm not sure how this affected the log.
The battery is new
The ignition switch was rebuilt etc.
The current MSQ is attached.

Please let me know & Thanks a million for your help :wavey:

Ok, these two issues may or may not be related. I just need the stupid car to drive my kid to school so I'd really appreciate some advice from you guys.

Hard cranking aside, the car stalls and refuses to start during the warm up cycle. So if I try to warm up for a couple of minutes and then drive I get stuck.

I pooped a couple of logs. Seems to me that just before the motor stalls the timing shoots up for some reason ,something causing a dip in MAT and PW. Bad wiring or a bad sensor on MAT? Causing PW to drop during a critical warm-up period?

I attached the log plus a screen shot.

I've no clue if this is a setting or what type of issue.

Thanks

This might be a bit premature but then again so was I LOL

I'm posting so it "might" help someone with similar issues.

Cold start up this cold morning was better. Of course I only got two tries before I’d say it is no longer a “cold “ start.

What I did-
Watched where the spark map pointer is when cranking and reduced those cells.
Took off 5 points from the cranking pulse numbers.
Increased the cranking RPM by 100
Still have to load the new firm ware…

Hoping for the best ;)

Did you ever nail this down?

Mostly fixed but it acts up once in a while. I would not rule out that the starter may also have something to do with it but don't want to change it .

I have seen literally, exactly the same issues you have seen.

Was the adjustments to the spark map what made it good enough for you to live with?

I'm sorry, I don't remember but it is simple enough to try if you are having the same problem. Just change one thing at a time.

See if this helps https://www.miataturbo.net/megasquir...startup-77785/