Ignition coil question

**iryshman** · 03-01-2008, 11:05 PM

The 67 started acting up with an ignition problem today. It started running like the rev limiter was kicking in when I was nowhere near the 6k setting.

At idle and while revving it in park it runs fine, no missing. But when I take it out on the road it runs fine at first but as soon as it warms up a bit, it starts missing.

It was dark out when I was test driving it so I popped the hood and happened to see some faint sparking at both of the coil terminals. The sparks weren't bright, almost like you could see it through the plastic and they were between the coil wire to the dizzy and the terminals. I figure the coil is shot so I'm gonna grab another one tomorrow along with some new wires.

Has anyone on the list run into this before? I've never had a coil spark on me before but I never really had a problem like this before so I never looked for it. Especially at night.

Thanks
Dave

**PaulS1950** · 03-02-2008, 06:28 AM

Arcing to the coil leads is fairly common. The cure is to replace the coil and use some dielectric grease on the tower and boot when you install the new coil. Dirt and moisture will build a path for the high voltage electricity to follow right to the nearest point - the terminals. Keep em clean and dry with some dielectric grease.

**iryshman** · 03-02-2008, 06:22 PM

OK, now I'm scratching my head. After replacing the coil and the spark plug wires the beast is STILL missing. I'm thinking that my MSD6AL box has taken a nose dive but didn't go completely over the cliff. I already tested the box by using the MSD test procedure and it does push a spark but AFAIK that only tests to see if the box is dead or not. I still suspect that it might be MSD related but since the box is not DoA I cant be sure without swapping it out. Does anyone know of another test I can do that will test the MSD? Besides buying a new one?

I prefer to test rather than just throwing money at it by buying a new one.

The test I used was MSD's Pull the coil wire and place .5 inch from ground, disconnect and jumper the green and purple wires, turn on the ignition key, pull the jumper and watch the spark.



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