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Misfire caused by Alternator?

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8.2K views 5 replies 3 participants last post by  And_44  
#1 ·
Hey there,

So after replacing many parts with other to diagnose a misfire in all rpm ranges I have a question.

The ignition coil/module receive there voltage directly from alternator.

My problem.... I get spark to all four ports on my coil, BUT with the wires attached I'm not getting enough charge through the wire that is furthest away on the coil from the +/- posts on the back to trigger my timing light, I can switch my wires on the posts and the no signal follows the one post on the coil and not the wires. I've swapped my ignition module with 2, and my coil with 3. All same results. The

So my question could the alternator when warm/hot be putting out a lower voltage to not put enough of a spark on the posts furthest away from the +/- on the back of coil?
 
#3 ·
I guess its a possibility if theres resistance/corrosion in any of the wires. I would do a continuity test from every wire from the alt but I don't think thats it. Its a cheap and easy to check so I would do that first before you put money into it.
 
#6 ·
Wasn't a double post to my knowledge. I had another post that was asking about the module and coil. And well after ruling those out had a question about the Alternator. Two different topics.

Turned out to be something unrelated.

But for those who do future searches. Yes a faulty alternator can cause a misfire/stutter. And when the alternator is subject to warm or heat it will create lower voltage for the ignition coils to create a strong sustainable spark.