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Hey guys, I need some help diagnosing a miss that appeared suddenly. My car is a stock r33 gtst, I put new plugs and a set of yellow jacket coil packs in it about a month ago. It was running fine until a couple of days ago when I went to start it and it was missing badly.

By disconnecting the coil pack plugs while it was running I found that cylinders 1 and 4 seem to be missing ( It runs the same with these 2 disconnected) Those cylinders continue to miss if i swap coils from other cylinders. I put new plugs in them as well, and even pulled the injectors out and got them cleaned and flow tested and they are still misfiring.

Any suggestions on what I should try next? I'm thinking the wiring to the coils or injectors but I'm not sure how to go about testing them.

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https://www.sau.com.au/forums/topic/319564-need-help-finding-an-annoying-miss/
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A mate had a similar prob, many dollars later & experienced tuners taking plenty of looks it turned out to be 2 broken wires in the loom he found accidentally by pushing wires to coil packs out of the way

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