Primary ignition waveform

Hi scanner thanks for inviting me it's a honor to joining her.. as the image described I have this waveform with no spike before the spark line this coil has been replaced tow time and the driver for it also has been repaired

thats interesting waveform looks like black marker and i was wondering exactly how you repaired the driver can anyone else chime in LOL !!

Is it the driver ..? I don't know who repaired the driver the car had came to my shop after this was done..

Hmm a plotting oscilloscope, fancy!
Anyway, from what I can see looks like a shorted wire or plug to me.

It's COP .. no matter if you Chang the coil or the spark plug still look the same waveform all other coil waveforms look normal.. sorry I don't save the original waveform from the scope I just draw it

Emhemd wrote: Is it the driver ..? I don't know who repaired the driver the car had came to my shop after this was done..

If the burn line is flat, like you've drawn it, it could be the driver is clipping the voltage. Maybe an incorrect component or the repairer got "clever" and installed circuit "protection". I'm wondering if 'scoping current on the coil driver wire to PCM would show anything??

Yes sir Matt T,, the flat line doesn't exist in the waveform ..

Emhemd wrote: Hi scanner thanks for inviting me it's a honor to joining her.. as the image described I have this waveform with no spike before the spark line this coil has been replaced tow time and the driver for it also has been repaired

There's a red box at the top similar to the picture I posted and circled.

If you could provide the information it asks for that would be very helpful and probably get you more help here in the forum as unless I missed something we don't know any specifics about the car, engines, mileage, symptoms, what's been done which at this point seems vague as getting into a box and repairing a driver should be done by people that know how to do that as at times it can create more issues than there is causing further complications.

IS the computer a rebuilt from a reputable shop within the industry as everything has to check good along the way otherwise you can have issues.

See below for the information requested for threads. Also include mileage in case I forgot to mention please.

if you've swapped cop coils around and the problem stays on same cylinder, then I'd check the power to the coil. Scope the power feed during crank and make sure it stays battery voltage, or load it with a headlight bulb.