Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
What has me concerned is the coils were arcing outside the coils. If any of those arcs were to make contact with the injector circuit, it would fry that particular injector driver. You have injector shutdown on #5 & 6. My thought is that's what happened. If your cam and crank signals and correlation are good, that pretty much confirms it for me, you have two bad drivers.
"an open mind let's knowledge flow in and wisdom flow out for a man who has neither never listens to those who have both".
Being wrong doesn't bother me, it's being right and not understanding why that does
Why would the injector work sometimes with a pulse and cut out randomly? Scanner Danner had a video on injector shutdown if the pulse comes back on restart the ecu is working.
It is a mystery, just like the vehicle, it would be nice and respectful to this site to answer with the y.m.m., you were asked a couple of times, I'm just saying
If the injectors only pulses after restart then stops, its the ecm... when I say the ecm, I'm referring to the driver, more correct, the transistor that pulses that particular cylinder injector. That driver is contained within the ecm. One for each injector. If its intermittent it could be the loss of driver signal from the cam sensor, a damaged reluctor and or wiring. The engine always runs, it just has a dead mis in the #5 and or #6 cylinder. Only way to tell would be to scope the ignition and injector pulse while running and review the waveforms. Correct cam signal waves would rule out the cam sensor and reluctor. Viewing the primary and secondary ignition waveforms can tell us a lot about what is going on in each cylinder. All the other injectors pulse so the problem is isolated to those two injectors. Testing ignition spark outside the cylinder is not always a conclusive test as combustion plays a huge part in the ignition process but you're sure you have spark and no injector pulse. Absent this, wiring is suspect and intermittent problems are the worse to find. You could have an open that occurs when the car heats up and more stress is put on the wiring or vibration that shorts a wire as the engine runs. If you watched Paul look for a wiring problem, you see how methodical he is.
I should have been more clear before. Not all cars will have the injector shutoff with an ignition problem. Again, Paul has many videos where he is diagnosing and raw fuel is being dumped into the engine.
Not all of us have the array of diagnostic tools that Paul is blessed to have so we have to make due with what we have and that can be and is frustrating for us DIY'ers. Keep the faith and don't be a parts changer.
"an open mind let's knowledge flow in and wisdom flow out for a man who has neither never listens to those who have both".
Being wrong doesn't bother me, it's being right and not understanding why that does
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