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Hi everyone,
I almost finished rebuilding my miata, but I'm having trouble getting the Toyota COP's to work. I 'bench tested' them in the car with the coils on top of the valve cover and they produced spark (all four coils), but at first I didn't notice the significantly weaker spark on coil B, and put everything together. When I tried to start the car for the first time in about a year, it had a hard time getting to run on its own power. As it turns out, it probably has too weak of a spark in cylinder 2 and 3, which explains why it runs really rough at 650 rpm (on 2 cylinders), and dies after a couple of seconds or when I feather the throttle.
I used the ignition test mode on megasquirt and noticed a really weak sounding spark on cylinder 2 and 3 (coil B) and a strong (relatively loud click) spark on cylinder 1 and 4 (coil A). I tried switching over spark plugs and COP's to different connectors to rule out one of them being faulty. I don't have a spare ignitor to test the system with the stock ignition by the way.
So my question is: What did I possibly do wrong to get such a weak spark on coil B, but a good, strong one on coil A?
And yes, I'm running wasted spark with COP's
I attached a log of me trying to start the car, if that helps get the issue resolved.
Update:
I played with the coils and different spark plugs a bit, and it seems that my old NGK plugs have a better spark than my brand new iridium ones, which I'm kinda pissed about but oh well.
I'm pretty sure it has decent spark right now, but the engine still dies after a couple of seconds or when you apply throttle. It seems to lean out, and it seems like it's too lean overall (which could not be possible with some cylinders not firing, right?)
I attached my tune to this, but I feel like it has nothing to do with the enrichment, since it doesn't even start and idle properly.
After checking the timing with a timing light I decided to hook the signal clamp up to the other coils and only cylinder 1 and 2 had a steady 'signal', cylinder 3 only had the trigger signal once every 2-ish ignition events and cylinder 4 has no signal at all (no flash on the timing light)
I feel like it has something to do with the loom I soldered, is there any way to check it reliably? Also, is there a way to check the coils individually?
UPDATE: I decided to redo the entire harness I made for the toyota coils, since I swapped out the coil that didn't fire with the one that did. After doing so the problem remained the same, so it has nothing to do with the coils, so it most certainly has something to do with my mediocre soldering work...
I also reopened the ignitor I gutted for the harness to check the connections, they seem to be okay, but I thought I'd ask if I missed any connections. I'm pretty sure there are supposed to be six connections, but why don't the toyota coils use the white and red wire?