1977 Ford F150 not enough spark from the coil?

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SNOHOBOY
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  • 1 POST
Electrical problem
1977 Ford F150 V8 Four Wheel Drive Automatic 125k miles

Hello...When turning my truck over I get NO spark what so ever. Now, As i turn the key off to stop it from turning over...I get just alittle lite spark which causes the truck (for a second) to sound like it wants to start. I've bought a new coil, new ignition module, new distributor, new plugs, new ignition switch, new starter, and new battery....These old trucks really dont have much for "electrical" going on under the hood...So, I'm really getting fustrated. This should not be a hard fix...you know? Please help me!!!!!!-TIM
Dec 18, 2008 at 3:07 AM
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BLACKOP555
  • ✓Experienced Mechanic
  • 10,386 POSTS
sounds to me like you may be getting constant -12v to the one side of the coil instead of pulsing -12v. which causes it to spark once the key is turned off and the power is lost. check for -12v with key on, off and when cranking. let me know what you find. also check the +12v to it.
Dec 24, 2008 at 3:45 AM
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