No spark on left side w/ Pamco

I searched thru the Pamco related topics but most talked of complete coil failure or Pamco board issues. I put a Pamco and his mid grade black coil on my stock 73 last fall, I have maybe 100 miles on the system. I have no spark on the left cylinder now. Maybe I had the ignition on w/ out shutting off the kill switch. Wouldnt have been long but I dont remember?? I have swapped plug leads w/ the different outputs on the coil and the right side always fires but the left remains dark. I have continuity from Pamco board up to all connections on the coil. I have not ohm'd out my coil yet, I needed to find some more patience before things got ugly Any thoughts on this issue? Thanks in advance.

When you swapped leads at the output, did you also swap the leads from left to right? If one side is firing, the Pamco is working. If your right cylinder fires regardless of which tower of the coil you are on, the coil is working. Swap the leads, then swap the plugs to finalize your troubleshooting.

So just to verify a few things.

You have taken out the plugs (one at a time is easier), grounded them on the engine's head and visually verified spark/no spark on the cylinders? Double checked the gap on the plugs? Doubled checked the condition of the plugs? Could be a fouled plug.

You have swapped right to left, one item pair at a time, visually checking for a spark each time.

1. The leads at the plugs.
2. The leads at the coils.
3. The plugs.
4. Fresh plugs, properly gapped.

The Pamco has a wasted spark, both plugs will fire at the same time, but only one cylinder is on it's power stroke. This makes it easy to swap things around to check for spark.

Doing all these things (one at a time) should reveal where the issue is (if it's electrical), even if it is a coil lead (which would show up when you left the plugs and plug leads and swapped the leads at the coils.)


~ Derek

Thx JD and Derek. So does the Pamco have a primary lead off the board for each cylinder or is it safe to assume that if one side is firing then the Pamco is doing all it can do and likewise with the coil? If you have high tension on one secondary post then you should have it on the other? This only leads to one answer and that is a problem either in the spark plug lead, cap, or the plug itself. If it's a wasted spark ignition then all the major components must be in order? That is a good start i'm guessing... Maybe the 2nd plug I grabbed from a pile of VW plugs is bad, I will check these things. Thanks much for the quick reply

If you have fire on one side every time the piston comes up, then the Pamco is controlling the field in the coil as it should. I suppose in a really crazy instance one magnet could trip and the other not, but I'd consider that an extremely remote possibility. If you spin test it you should be able to see if you are firing once per revolution of the cam, or twice, even if only one side is functioning. I'm thinking you are looking at a bad plug or plug lead at this point. I guess it's possible for one tower of the dual output coil to fail, but that, again would be much more rare than a bad plug wire or a bad plug. Sometimes merely dropping a plug can fracture the ceramic and cause the lug to spark up inside the insulator sleeve, rather than at the gap.

What a dumb dumb I am, I just posted a thread with almost the same title. My apologies.
However mine is a 277 so a bit different

Saggs said:

Thx JD and Derek. So does the Pamco have a primary lead off the board for each cylinder or is it safe to assume that if one side is firing then the Pamco is doing all it can do and likewise with the coil?

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There is only one trigger lead from the Pamco to the coil, the Pamco triggers the coil, which fires both plugs every time. If one side is firing the Pamco unit would seem to be functioning properly. As for the coil, I can't say. Whether one coil post could go bad and the other remain functioning I do not know but should be easy to spot with the steps I listed.

Saggs said:

If you have high tension on one secondary post then you should have it on the other?

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Electrical resistance? I do not know, sorry, but see above...

Saggs said:

This only leads to one answer and that is a problem either in the spark plug lead, cap, or the plug itself. If it's a wasted spark ignition then all the major components must be in order? That is a good start i'm guessing... Maybe the 2nd plug I grabbed from a pile of VW plugs is bad, I will check these things. Thanks much for the quick reply

Click to expand...

Plugs are a cheap and easy thing to swap, use fresh ones and gap them properly. If you swap the items one at a time from what I listed in my first post, you should be able to isolate the problem.

jd750ace said:

I suppose in a really crazy instance one magnet could trip and the other not, but I'd consider that an extremely remote possibility.

Click to expand...

What other magnet?


~ Derek