[Trevor]

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Since composing the previous post, I have again carefully studied the wiring diagrams and find that the igniter and coils are switched by the igniter in the negative, rather than the positive, supply leg.

This means that you should ignore my advice:-

"Although you can't check for a possible nasty voltage from the alternator, with the ignition on, you can verify that the igniter is getting full battery voltage."


The igniter receives positive voltage, via the six trigger circuits from the ECU, and switches the negative ground circuit to the coils. This rules out any problem relating to the alternator.

The coils all receive positive voltage, via a connection at the second 8 pin plug connector within the loom, which runs from the igniter to the coils as I mentioned earlier but appears not to have been found. With the ignition energized you must find and check for voltage at this connector on the plug side at pins 5 can 6, and the black/white wires which become a common connection on or after entering the loom.

It turns out that I did not make a typo and you will have to accept that it is difficult to verbally communicate regarding this sort of complex problem and patience is required, but we will get there. LOL

At this point I am not convinced that the problem is confined to the igniter. When changing igniters your could have corrected some obscure faulty intermittent connection which again failed later. Give this some thought.
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