Analyzing Ignition Waveforms

Hello,

I have just been scoping out ignition waveforms. I have a lot of questions. Can anyone recommend some good resources for further analysis? I have the scannerdanner book and I had a premium membership and watched all the videos. But I still have questions. Heres a few weird ignition event captures. Whats anyone think of these? All the same vehicle. All at idle.

You may want to look at this thread:

www.scannerdanner.com/forum/post-your-re...questions.html#29114 .

yes, thanks, been watching those TST seminars...

But take a look at the pics above.
The middle picture is good waveform.
The other two both show something different going on. Im not sure what.
But when I take a recording of a bunch of ignition events, should I disregard the weird looking waveforms and only focus on the good. Or did I catch something bad?

Joshasta, I've got your three captures here. I'll give you my best WAG's. Given that I don't know the vehicle (other than a Toyota) or the ignition system.



This one looks pretty clean, IMO. Normal amount of current draw. 1.5-ish ms burn time. Burn line looks normal. If this was taken off a Toyota COP, then this is probably about as good as it gets with secondary testing.



Best guess, the secondary probe placement on the coil isn't perfect. The characteristics are there, but the amplitude of the burn line isn't like the first.



This one *might* be misfiring? :huh: There's no clearly defined burn line. There's also no coil ringing at the end of the (non-existent) burn line. Again, probe placement may be a factor. I see this type of waveform on distributor systems when placing the probe on individual wires.

Right on, Thanks Tyler.

This is from old '94 Toyota pickup. 3VZE. Distributor with electronic pickup.
I was moving my secondary clamp pickup around on the wires. Sometimes I could have my clamp placed further away from the distributor than other times...
But, yes, I was wondering what's up with the burn line on these 2:

Here's another good resource, it's Mac's old book from the Allen Institute. Jim Morton shared this with me a few years back!!!!

drive.google.com/file/d/1wIbSpsoTrk-CtIL...WTE/view?usp=sharing

sweet, thanks for sharing!