Been having trouble with misfires

This car is completely stock except for a BMS chargepipe, and DCIs.

This issue began with constant misfires on Cylinder 4 which was a result of the teflon seal on the injector literally missing. I then replaced sparkplugs, coils, and injectors but and still having problems.

the car starts and drives just fine now until you put some load on it (get into boost, hills, normal highway accel, etc. ) then it stutters and shakes and barely accelerates. If it does this enough it then deactivates cylinder 4 until i either clear the code or restart the car. Im getting 29CD0 and nothing else.

i have replaced coils, sparkplugs (gapped), injectors (index 12, coded), and now as a last desperate attempt a HPFP. I am out of ideas as to what could have happened.

ive already tried moving coils and plugs around even swapping to one of the old coils. The misfire always stays in cylinder 4.

There is the tiniest knick in the wires leading to coil 4 however, the copper braiding in the wire was still completely intact they have been insulated with heat shrink and I do not think this would be an issue.

I am completely out of ideas as to what to do, any suggestions?

 

bump for the morning

 

When was the last time you walnut blasted the valves?

 

it has been done recently. Who ever did it left the walnut media all over the side of the engine. When i replaced the HPFP i got a good look at the valves, theyre still pretty clean.

took it to a specialist and theyre stumped. They seem to think something is wrong with the DME. I have the MSD81 Index 3 DME. I will be replacing it as the next step.