Warm restart and idle issues
 

I'm starting a new thread as a continuation of my questions from https://www.miataturbo.net/megasquir...s-79819/page3/ because it appears my issues are moving in a different direction and I don't want to derail that thread.

To summarize, I previously wrote:
Then Braineack wrote back:


And I wrote...
I poked around a bit today and have some more to share. I'll put that in the next post.

So I looked through my spark table first because of the feedback about the massive amount of advance. First, my tune is configured with a 6* offset, which I understand to mean that I should remove 6 from any of the timing numbers I see in the log and my spark isn't as advanced as it appears.

Also, the numbers in my ignition table are more advanced than in base maps I found online, but wouldn't I expect that if the table had been tuned on a dyno? My tuner told me previously that they played with the timing numbers until they faintly detected pre-ignition and then backed off from there. So how much advance is too much?

Next I worked on the mixture in the fuel map to verify it's correct at 1200-1400rpm as suggested. I checked AFRs in that area and hand tuned my Idle VE to be ~14.7.

Then I noticed in the previous log that the AFRs were way lean for a while after the EGO came online and then converged to ~14.7 after a few seconds. I poked around and found that EGO Delay After Start was set to about 30 seconds, which was way longer than it took for the O2 sensor to come online. I dropped it down to 5 seconds and specified elsewhere that any reading below 8.0 should be ignored, which covers me before the sensor comes online. I figured this would cause the MS to pay attention to the EGO input as soon as it was available. It looks like this has improved the situation.

I'm attaching the latest log file so you can take a look. Interestingly, the engine is good and hot now and it appears the injectors are handling it OK. If this all looks good to you then I've got another question to ask.

Incorrect. The 6* makes the log and timing tables correct for what your engine is actually getting.

Also your tuner is tuning WOT spark and we're discussing idle spark.

No offense but it's pretty clear you're new to MS and TS. Which is great! Everyone starts here. I'd read around as much as you can before making any assumptions or changes toyour setup.

Hmmm...so my timing really is way more advanced than in the base maps. I'll ask my tuner about that.

Still, shouldn't a dyno tune have dialed in the ignition properly? That's what I thought I was paying for.

I'm attaching my ignition table for your comments.

Yeah your timing table is a good bit higher then it should be. Just for reference timing at idle is generally between 10-17 degrees.

Yes a good tuner would have tuned the spark table all over. From the looks of it, I don't think your tuner is very good.

Well, thanks for the honest feedback. That's the only way for me to know whether things are running as they should be. Can you point me to an ignition table that's closer to what I'm looking for?

Also, I figure I can't just put in new values in the table, right? Wouldn't I need to retune all kinds of stuff, including the VE table and WUE?

quick test: go to the 3D view of your timing table. Your WOT cell (this is the 100kpa row with N/A engines), should have a similar shape as your dyno plot. So according to that timing table, you have a perfectly linear power curve, no loss in power until redline.

Most Miatas turbo or not don't do this. Unless you're supercharged.

Yeah don't touch your tune. Especially if someone else tuned it. If there's any difference and it blows up, you'd be liable. They did a very basic power tune my guess so hopefully you didn't pay more than ~$350. that should be ~$100/hr for the dyno, take 1-2 hours, and a little extra for their time.

I'm not saying it's bad or unsafe, but with your experience I wouldn't change it much before we or someone local helps out a little.

hey guys, i work at the shop that tuned the car, im the one that installed the setup, and then started fixing issues in the tune after it initially left, im here to help so any and all feedback is appreciated, it will help me learn as well, im not the actual tuner at the shop but i also have a megasquirt miata (n/a) and really want to help get Ace car running properly and make him happy

Oops and here we are all bashing you.

The timing tables just Raise a few eyebrows, especially that jump from 33 to 19, and why is it at 33 at all? I thought DIY's MSM base map was high at 25. I personally do 20. The stock 10 seems a little low the more I tune idle.

Thanks for the pointer. Yeah, I wasn't planning to play with the timing table unless I got specific direction.

My tuner spent a lot more than 3 hours on the tune, especially since I know they've run through it twice. I can't explain what we're seeing at this point but I appreciate everybody's help in getting to the bottom of it.

I'm attaching a 3D view of my ignition table for your review.

It's just a linear table, which is a bit of a novice move.

As you change timing, let's use advance for this example, you'll see some rpms gain power and others stay the same. Add 2* across the board and see only gains between 3 and 5000? 0-3 and 5-redline should probably revert back to the old timing numbers while 3-5 keeps the new timing.

Keep doing this over and over again and you'll get a fairly typical Miata dyno plot.

timing is something im not 100% with yet so im not surprised i made a novice move on that one, was trying to stay safe and get MPG out of it as Ace was already happy with the power output of the car. didnt want to do anything crazy. so looking at his map what advice would you give me for adjustments that will help with his warm restart issues?

clearly your tuner wants you to blow your motor. Or simply doesn't know what he's doing, is charging you for his "expertise", and will point the blame when your motor does finally melt.

at 100kPa you have about ~13° more advance than the stock ECU.

in boost, you've never retarded past the OE spark timing. A good rule of thumb is 1° retard for every 1-2psi in boost...

just do the math here...


I would literally reduce your entire timing map by 10°. It would still be aggressive, but it would be within reason.

when I add in 10° to the timing map I use, your current is still more aggressive:
https://www.miataturbo.net/attachmen...ine=1455984501

I'm seriously shocked your motor hasnt blown yet.




please just post your entire MSQ.

Ooh yeah i follow that rule of thumb too. If you set your timing tables with 2 psi deltas (14ish kpa) you can get your timing curve at waste gate safely and then have a good idea for max curve.

I sent you an email with his MSQ. He sent it to me last night, but I have not had a chance to look at it yet.

First thing I would do though would be to upgrade to firmware 1.4, instead of staying on 1.3.4.

Thanks for the feedback, guys. Let's assume for the sake of argument that my tuner isn't trying to blow up my car and that we have a difference of understanding about what an ignition table should look like. I'm new to the Megasquirt so I'm clearly learning how it works. But I've got some background with the Link so I'm happy to share that I don't feel *totally* clueless with this stuff. As you can imagine, I feel stuck in the middle here and I'm looking for truth. I really appreciate everybody's help in getting there.

So I've gone ahead and uploaded my tune. I'm looking forward to your feedback.

Meanwhile, it preliminarily sounds like I should back off the timing across the board. Let's say we collectively decide that's the right thing to do as a first step. What other changes would we need to make to the tune? I figure I'd need to retune the VE table at least, right? How extensive would any other changes be?

Regarding shuiend's suggestion:
My understanding is that you can't just upgrade firmware on a Megasquirt like on an iPhone because the tune doesn't come over. You have to apply the new firmware version and then manually copy over the configuration. Is that correct? Would somebody please point me to a process for upgrading the firmware?

Nope it copies over with few errors. Back in the day it was stuff like "tune has 1.0, firmware has 1.00", but it's a little more complicated now. I think it works with just one round of I'm-freaking-out-bro warnings.

I'd load a base map timing table and double check sync, then retune for max power using a slightly different method than before.

I dont like this:

https://www.miataturbo.net/attachmen...ine=1455988683

you're basically adding 8°-5° of advance as your motor warms up. that's just odd, you should only be using this below say 60°F.


spark table 3 looks pretty good, one does not.

https://www.miataturbo.net/attachmen...ine=1455988683

looks like they setup table switching and why you have fuel and spark tables 3 activated.


https://www.miataturbo.net/attachmen...ine=1455988683

do you even use this?




what type of injectors? i see you have larger ones, but what brand?

https://www.miataturbo.net/attachmen...ine=1455988683

I dont like that deadtime curve compared to what I've seen from different manufacturers. seems very conservative and could lead to underfueling.



ASE and warmup enrichments are very very low:

https://www.miataturbo.net/attachmen...ine=1455988683

https://www.miataturbo.net/attachmen...ine=1455988683

you can autotune warmup if youre lazy.


priming table is crazy long, ever notice how long your fuel pump runs when you put the key to ON?

https://www.miataturbo.net/attachmen...ine=1455988683



your fueling algorithm includes AFR, I'm not the biggest fan of your AFR map

https://www.miataturbo.net/attachmen...ine=1455988683

your VE table actually looks pretty standard, like it was never tuned for that AFR table correctly imho. goes with what i was saying before about not enough fuel in certain spots, that coupled with the piss-poor warmup and ase tables isnt helping.

you need to copy your spark 3 values into your spark 1 table PRONTO.

Wow.

Like wtf?

I don't like cold Advance and wue at standard operating temps, but that's just me.

I also put that 210 cold advance to -10 starting at 205-207, so if it starts to overheat it reduces power a bunch. I do that for wue fuel too.

But that's besides the point. Braineack brings up some good questions.