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Coil discharging.

 
Old 05-14-2019, 01:33 PM
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Default Coil discharging.

94 F150, Just bought a new coil (second one), and after the engine is shut off is sounds like it is discharging.
any ideas?
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Old 05-15-2019, 12:35 AM
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I've never heard a coil discharging, even when it IS discharging. What sound are you hearing? Since it's a cheap aftermarket replacement coil, maybe browse the junkyards for a nice original one.

You should remove that crappy red pierce tap and repair that wire before it breaks. You should also insulate the bare wire going into the capacitor, or just get a new capacitor.

And it will make maintenance & diagnosis easier if you keep the engine clean:


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Old 05-15-2019, 06:40 AM
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It is not a capacitor and does not store a charge or discharge after the energy is cutoff on its primary.

Last edited by raski; 05-15-2019 at 06:44 AM.
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Old 05-15-2019, 09:27 AM
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The big blue thing in the middle is the coil. The little silver cylinder below it with the bare & frayed black wire going into the end is the capacitor. Look at C1017 in all 5 of these yearly wiring diagrams:


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Old 05-16-2019, 05:24 AM
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Capacitor is used for RFI reduction for AM reception with the radio. Has nothing to do with ignition itself and the engine would run no differently without it. After 26 years and being exposed to engine heat, there's an excellent chance that C1017 has already dried up and is basically "open", losing its filtering ability.

Last edited by raski; 05-16-2019 at 05:36 AM.
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Old 05-16-2019, 10:24 AM
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C1017 is a connector - it's always dry, and there's no reason to think it or the capacitor is open. And I didn't say it had any effect on the symptom - I said it was worth covering that bare wire so it doesn't become or cause a NEW problem.
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Old 05-16-2019, 08:17 PM
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Originally Posted by Steve83 View Post
C1017 is a connector - it's always dry, and there's no reason to think it or the capacitor is open. And I didn't say it had any effect on the symptom - I said it was worth covering that bare wire so it doesn't become or cause a NEW problem.
Sorry, I thought from the schematic, C1017 referred to the cap.
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