Spark output in test mode, no spark while cranking
 

Hello everyone! Let's start with the details.

Megasquirt 3 on v3.0 board. The Miata is a 1990 with minimal performance parts. Currently trying to get it started on MS but I don't seem to get spark, as verified by a timing light.

I have full sync, and the timing light shows spark when I use test mode, but when I go to crank the timing light will not flash, except once when I stop cranking. The LEDs on the Megasquirt for spark outs are on and flashing, but the timing light does not.

I currently have the injectors unplugged while I figure out why it's not sparking. I don't expect that would have any effect, but thought I'd bring it up just in case.

I'm also attaching my MSQ.

Any help would be greatly appreciated!

You're not using an expander card? I dont see anything in the MSQ that shouldn't allow spark while cranking.

So I'm going to have to assume it's the cam/crank inputs and/or spark outputs

No expansion, just plain MS3.

I'm pretty sure there has to be spark... when I plug the injectors back in, cranking is labored and it will occasionally kick back on the starter, or it might try to start and then fall back down. Is it possible during cranking that there's not enough voltage in the spark wires to trigger the timing light? I'm pretty sure my trigger angle is off, and that's all that's keeping it from starting.

Here's a video of what it does while cranking. You can hear it backfire a couple times, so there must be spark... just need to adjust trigger angle?

Miata trying to start - YouTube

Problem solved. Cranking voltage was not enough to power the timing light. I was getting spark while cranking, it just wasn't shown by the timing light. The reason the car wouldn't start was because I had my spark outputs set for MS1, when they needed to be crossed for MS3. Car starts now :)

yay

:brain: