2014 3.5 Ecoboost
I had consistent misfiring on cyl 3. I swapped coil 3 and 1, and the misfire moved to 1. I replaced the coil with OEM. It improved the rough idle and motor-shaking symptoms. But look at this forscan chart... Cylinder 1 is the new coil. This is the acceleration of cylinder PID at idle, a rev up to 2,700 rpm, and return to idle. What's your analyis?

 

Which cyl is the purple line?

 

It’s #6

 

I have never used Forscan so I have no idea what I am looking at.

It doesn't look like a typical primary ign waveform. Where are you getting the signals from?

 

This is the acceleration cylinder PID. I can connect the drop on cylinder 3 and 4 to misfire. I'm not sure why #1 is so volatile vs. the other cylinders more steady idle numbers. I replaced the plugs and it's running smooth but I get the misfires on #3 and #4 under load, triggered at about 2,200 RPM or 16% load. I'll change out all of the coils. Previous owner put in MSD so I'll put in OEM.