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I am trying to help a buddy that has a TT swap. The problem is that the #5 cyl fires one second and then doesnt fire the next, Then sometimes it fires for a decent amount of time and runs great then starts over again. This is at idle and while driving. We have tried different coil packs on #5, tried switching a known good working Igniter, resistor pack, new plugs. We have tried puting the #6 connector on the #5 cyl and the #5 connector to #6 and now #6 doesnt fire. So I would assume the injector is firing in #5 cyl fine. Also the voltage to each coil coming out of the ecu is all the same @.13 volts. So I would think the problem lies between the ecu and coil packs. I am not familiar with the wiring as I didnt do the swap. So does the coil wires from the ecu go to the ignitor and then to the coil packs? We did test the voltage coming out of the two wires going to the coil pack connector. When we ground the voltmeter and test the two wires,

Good coil pack wires(1-4 and #6) reads 13.4 volts on one and .35 volts (fluctuating from .25-.35V) on the other. The #5 coil pack reads 13.4volts on both connections and doesnt fluctuate. This is what makes me think that the voltage is the problem.

A cupple of questions for the wiring guys.
1. How does the ecu tell the coil packs when to fire?
2. How do the wires go out from the ecu and end up at the coil packs?. This might help find the bad connection or touching wires for #5 cyl.

Any suggestions would be greatly appreciated.

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