Will not start no spark at coil

1979 JEEP CJ5
150,000 MILES • 4.2L • 6 CYL • 4WD • MANUAL
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WATKINT1
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About three days ago I drove the Jeep around town. The next morning it would not start. I have a spark and there is no spark coming out of the coil but I have 12 volts on the positive side of the coil. Any help?
Nov 13, 2018 at 3:29 PM
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ASEMASTER6371
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Good evening.

If you have a test light, check for power on the negative side of the coil. If you do, crank the engine and see if the light flashes.

If it does then the coil is bad.

If it does not, then it could be the pick up in the distributor or the ignition module.

Roy

OPERATION
Manifold vacuum and carburetor ported vacuum are both used for the ignition spark advance mechanism. On some engines, a coolant temperature override (CTO) valve determines the correct vacuum source, according to coolant temperature.

On other engines, a non-linear vacuum regulator (NLVR) valve combines manifold vacuum at idle speed and carburetor ported vacuum at a ratio proportional to the amount of throttle opening.
Nov 13, 2018 at 4:11 PM
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WATKINT1
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I do not have a test light, but I have a volt meter. Can I test it with that?
Nov 13, 2018 at 4:54 PM
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ASEMASTER6371
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 52,796 POSTS
No. It will not react quick enough.

You can get one for under ten bucks at a parts store.

Roy
Nov 13, 2018 at 4:56 PM