A Ford Truck came in today with a complaint of a misfire. The problem was confirmed during the initial test drive at approximately 45 MPH and above and under moderate load.

No codes were stored (big surprise there), but Mode $06 data revealed misfires mostly on #1 and only a few on #9 (a V10).

Since #1 is so easy to access I removed the coil and plug and found a very worn original plug.

I always check COP coils on the bench and check them with my handy dandy KD 2632 Portable Ignition System for voltage output and leakage.

This is what I found on the #1 coil. [Ignition leakage test] All the other coils were fine. The output was strong but the boot was leaking so I replaced the #1 boot and all the plugs.

Thanks for reading, iATN is awesome!

Phil

Phil from Oregon

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