99 miata crank but won't start
 

Just finished installed MS2E. It was originally configured for 700CC injectors. I changed the tune to 350CC injectors. I still cannot get it to start.

It was crank but not fire up. I've attached a copy of tune and log while trying to start.

Any ideas would be greatly appreciated.

I'll be the first:

Get us a composite log while cranking

When I was trying to do the composite log, was getting a lot of data empty messages. Let me know if this what you need to look at.

Also are there any other changes that need to be made when changing the injector sizes? I bought this but it was never installed. But the tune was setup for larger injectors. All I did was change the CC size from 700 to 350.

I am making progress. Car starts but dies after 3-4 seconds. Almost like all the fuel has been cut.

What are your AFRs looking like when its dying? Is it leaning out?
Your ASE (After start enrichment) or WUE (Warm up enrichment) could be incredibly out of tune if they're from a basemap (and if you're not running stock injectors it can also be funky).

I will have to check it out today.

Here are my ASE and WUE graphs. I may also need to change my injector dead time. I am running 350CC EV14 fuel injectors.
Dead time is set at 1.0
Battery Voltage Correction is at .2

So I tried it again today. I moved my calculated fuel slowly from 8.6 to 10.5. The only thing it did was make it stay alive longer.
What i am noticing is that when it is dying, it is on the rich side, 11 AFR. I am getting the spark cut to go red in turner studio.
I plugged in the stock ecu and it fired up and idled without any issue.

I am using the base map that came with it from Rev (I bought the ecu from another user). Could the VE and Ignition Tables be off? The base map originally included was for 700CC injectors. My injector size is 350cc. My guess is I need to reduce the values in the VE table to better match my injectors.

I am still getting the situation where it starts, goes for 4 seconds, then dies. When it dies i notice that the AFR is 21.7 but I think the reason for that is my gauge AEM 30-4900 is going through a boot up because the car has just started. Is the ms2e recognizing the high AFR and shutting down the car? Am I on the right track?

Well after working on the tune for a few hours last night, the car will start but only idles for about 4 seconds before dying. So basically I got no where. Can someone much smarter than me look at these screen shots and let me know if there is anything obvious that is wrong with my tune?

Do you notice loss of sync?In the logs you posted, some cam sensor errors were reported.
Why do you run 31Hz as idle valve frequency? Do you use a seperate board to multiply that? Nb valves run more like @480-500Hz

I kept the idle valve frequency because it was like that on the base tune. I think the Ms2e's do have a something that multiplies this number. I can try and set it to 480-500 and see if it does anything. In regards to the cam sense error, what is the best way to troubleshoot? Should I think about changing out the cam positioning sensor?

When I put the stock ecu back in it idles fine.

For the cam sync, you can attach a composite log of the car starting and running until it dies.(Try again)
For the idle valve, is it perhaps too noisy with current frequency?
You can try to unplug the iac valve and see if it idles just off the tb idle screw(you will need to loose the bolt a bit most likely)
You need to calibrate your iac valve anyway.

Thanks for the information Akina. In order to calibrate the iac valve, don't you need to the engine to be running? I will try to get a composite log today.

Yes, you need the engine running, then use the idle valve test mode to find out the operating DC% range of your valve and fill the data in your closed loop idle settings and initial values table.

Hopefully I can get the engine running today to fill in the data for closed loop setting. Right now I am using open loop to just try and get the car to idle.

Really getting frustrated with this. Today I was able to get the car to start a few times, ran really rich for about 4-5 seconds, then died. Tried to make some changes and now it won't start at all. I wasn't able to get logs when it was starting. I did get logs "trying" to start it. I've attached those.

After I was unsuccessful in getting it to start, I put the stock ecu back in and it started easily. I swear, if i could pay someone to give me a tune that would work well enough to get this car to my tuning shop, I would pay them.

Need some help on some starting values for the Fuel VE Table. The injectors are EV14 350cc. They came with a kit but here is a link to them: https://gramsperformance.com/g2-99-0123.html

I's using 1.1 as my injector dead time. I've tried everything from .5 to 1.2 and nothing seams to work better. My idle values for Fuel VE Table 1 are around 70. My required fuel is 8.6

If anyone can point me in the right direction I would be so happy. I've read through the manuals but I couldn't figure out how to come up with the correct starting values for the Fuel VE Table. Also I grabbed the Cranking Pulse / AF Enrichment from a post I found by Braineack.

If there are any tuners out there that think they can help me, I would be more than happy to compensate their time.

Try using falling edge as ignition input capture.

Thanks Akina. I was looking online and for a 99 Miata I think it is supposed to be rising edge.

Atleast according to this page: https://www.diyautotune.com/support/...0-mazda-miata/

repost

You may want to just break down and pay a professional to help if you are stuck. I ended up hiring Ken Hill to help with my Hydra. Not sure if he does MS though. Ask on here and I'm sure someone can point you in the right direction.

Thanks Luke. I might just end up towing it down to a tuner that isn't too far away. Or I can drive it down their with the stock ECU and watch the AFR's really carefully.

After a few days of not being able to get it started, I was able to start it today. Again for just a few seconds. I am getting a few warning lights when it's cranking...

Getting Spark Cut in red and occasionally knock light.

Also should I be using batch injection instead? I have not modified my wires / coils / etc. All still stock.

Im having the same problem on my 99 miata with the base map. Just installed MS and car just starts and dies. let me Know if you figure something out.

Are you running stock injectors?

No, batch injection is for 90-93( we usually make this sequential also with ms)
Check your crank sensor, it's wiring and the sensor's distance from the wheel. This is where your problems lie most likely.

If it starts normally, idles for a couple of seconds and then dies, it is most likely a fueling issue(Req fuel, ASE, Idle VE Cells etc)
In Aaron's case, the car doesn't start most of the times.

If the car starts easily with stock ecu, could there still be a problem with the crank sensor? I will check out the sensor, distance from wheel and wiring today.

Strange as it may seem, I have witnessed such case, in a nb, like yours.

Hey. I got the crank angle sensor check engine light two months ago. I cleaned it (it was full of crud) and gapped it and then reset the code. It hasnt come back since then and ive driven the car probably 1.5k

Having issues with my idle (first start after installing MS yesterday) It cranks and turns over but dies right after. Seems to run rich before dying. If i keep throttle on 2k or more it keeps running at around 14 afr. At first I thought timing but timing was at 8 degrees so not too far off. When car dies it goes to 11 AFR. What do you think?

I think you should go back to your thread instead of mixing your unrelated issue in with the OP's. No one can keep anything straight when you're both posting about your problems in the same thread.

Sorry. I'll fly away.

I checked out the crankshaft sensor and the wiring was good. The gap was about the size of a credit card and and it was plugged in tightly. That being said, I think I will order a replacement as well as a new camshaft positioning sensor.

Before i installed the megasquirt, I was running a system that was similar to a vodoo box. About a month ago a strange thing happened where I would be going down the road anywhere between 2000 and 4500 RPM and I would lose power. Sometimes it was while I was on throttle. I think I might have a problem with one or both. Atleast I hope that is the problem. I think I have my tune to a place where I should at least be able to idle.

Also is it normal while starting / idling (for 5 secs) to see a 6% knock reading?

Also thanks to everyone posting in this thread. Appreciate the feedback / recommendations.

1mm gap is usually fine.
Do you have a real knock sensor installed?

So todays update...

I was able to get the car to start and run for 3-4 seconds. I could repeat this over and over. Of course didn't think to get a log because I was playing with tables.

Then the battery went dead.

Charged it back up and didn't make any changes....and....It wouldn't start.

I was getting both Fuel Cut and Spark Cut to light up when cranking. As soon as I stopped cranking I would get a big fat sync error 32. I really hope all my problems are related to either the Camshaft or Crankshaft sensor. Should have both mid week.


I won't be working on the car tomorrow as I have an Autocross event with my nice behaving car.

Changed out the Camshaft and Crankshaft sensors. I was able to get it start today and idle for about 3-4 seconds. Here is the composite log I got.

The more and more i think about it, not sure what is happening but I think the tune is good. I can get it to idle at around 13 for the first two or three seconds before it dies. Could there me something else that is causing the engine to shutdown almost always at 3-4 seconds? I have played with all the idle settings. more fuel, less fuel. Nothing seems to make a difference.

Is there something that changes to the programming inside the megasquirt after 3 or 4 seconds? Also could living at 6000 ft have an effect? Maybe something that needs to be changed to the barometric settings?

Can someone much smarter than me take a look at this composite log and let me know if there is something wrong? Still trying to chase down this problem. I can usually get it to start. Sometimes I need to give it a little throttle but it always dies at the same time. Maybe I have an ignition problem?
Just a few things I tried today but didn't make any difference. I unhooked the idle control valve. It would start but died at the same time. I changed the tune to open loop warmup. Same thing. Would die at the same time.

Any help would be greatly appreciated. Also I am not getting sync errors anymore. Except when the car dies. I read that it is normal to get a sync error when the rpms go back down to 0.

For every 4 blue lines you need I+II green ones between them. Every composite log you post seems different, are you sure you are using proper settings?