High tension leads with skinny plug wires

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High tension leads with skinny plug wires

Postby blakestreet » Sat Aug 20, 2016 3:14 pm

Hey everyone, I brought my pico and laptop home this weekend to practice and I was taking some "good waveforms" last night on my 2000 toyota 4runner with the 2.7. My car runs just fine, no misses, but I had a hard time getting a consistent secondary ignition pattern with the high tension leads on the scope. In fact, I actually squeezed the clamp and tilted it to get a better pattern on some cylinders, sometimes that made a difference, sometimes it made it worse. I planned on taking a plug out today, while my car is cold, and closing the gap and also opening the gap so wide that the plug can't fire, to see what some known "bads" look like and save them. But if I cant get a good baseline with my skinny wires, what is the point? Has anyone also experienced this? I have stock toyota wires and there is a huge gap between the wire and the lead clamp. If I hold it just right, I can get a good waveform, but that simply isn't an accurate diagnostic tool.

Any thoughts anyone,

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Re: High tension leads with skinny plug wires

Postby Alan » Sun Aug 21, 2016 8:32 am

Hi Blake,

If the wires are skinny then the problem is that they are not in the center of the clamp. Try wrapping a bit of something non conductive around the lead first - cardboard / tape etc.

Also if you can capture the primary voltage at the same time - its really educational to experiment with plug gaps etc whic viewing both waveforms.

Please also post any interesting waveforms!

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