Single spark when cranking then no ignition
 

I am having an issue with getting a single spark when I first crank, then I am not getting any spark from the ignition (coil packs).

I believe this is tied to the issue I was having of the spark blowing out at mid/high rpm, but I am not sure.

I was trying to adjust my timing to correct this issue and after adjusting the timing though megasquirt (and rewiring my fans) I got an issue of not appearing to get spark on hot start, but cold start was fine and it would run hot.

I let the car sit for a couple weeks and now I am only getting a single spark (cylinder 1) on first crank, then no spark. Using a "dummy light" there is power at the crank angle sensor, ignition and ignitor. However, I am not seeing any pulsation on the "dummy light" from the signal wires to the coils. I have also checked this on cyclinder 1 and 3 (I believe) with grounding a spark plug to look for spark and got the same results as the "dummy light"

My ampmeter is not working (I ordered a cheap one and a really cheap old Fluke) to help for future electrical issues.

I have trial fitted an igition coil and I changed the crank angle sensor (both with used parts from Johnmatt that should be good, but the problem did not change with either part.

I am kinda stumped, I could try a ignitor, or tearing into the megasquirt to look for a blown component, but I am fairly lost as to what to do. As far as I can tell there is a lack of sigal to spark.

I posted about this same topic under a thread for a 1.6 that was having spark issues on crank, but his appeared to be timing not total lack of spark.

Thanks for reading this overly long post.

Did you hook the timing light up to another power source and verify that way? I tried ground the plug and in the daylight I couldn't see the spark from anywhere outside the engine bay. So I thought I wasn't getting spark, then hooked up the timing light and only got the single spark on the first revolution, then none. Which I thought was backing up the "no spark" - but then remembered a few years back of being suckered into the same scenario. Usually if you get that first spark, it will continue to spark. IOW the hardware IS working. And regardless of what the ign timing is set at for the cranking cycle it would still try to throw a spark.

Jump ten and grd in the daignostic box and trun the key to on. See what codes it throws and reference them to the codes in the miata.net garage section.

I will check it out again tomorrow with a different power source, but I am pretty confident that there is no spark.

I am running the car on Megasquirt and don't think that I can get any codes out of the diagnostic port. I did not wire in the Megasquirt, but I am pretty sure that most of the wires to the ECU are no longer connected.

I created another thread on this a little bit ago in the megasquirt section to see if anyone has ideas if the issue is megasquirt related.
https://www.miataturbo.net/forum/t37409/

Thanks for the tips!

sorry for posting a link to this thread, I had optionally asked for advice in another thread not on the megasquirt and thought that someone replied there:
https://www.miataturbo.net/forum/t37005/#post433796

Do you see an RPM signal in the tuning software while cranking? If so, what's the signal look like?

I will hook up the laptop and check the signal. Not sure if I can see the signal wave or if I can just get an RPM readout.

I finally figured out my problem and it makes me feel like an idiot, my megasquirt was partially unplugged so it was not sending a signal. I plugged it back in and now it works!