Number eight spark plug not firing

1988 CHEVROLET 1500
625,340 MILES • 5.7L • V8 • 2WD • AUTOMATIC
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GLIDERBOY19
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I changed the distributor, wires and plugs after having an intermittent skip in the engine. The old distributor was in bad shape. After completing the install I cranked the engine and the skip was still there all the time. I checked the compression on #8 and found it good. Tested with a separate plug and plug wire and found no spark at #8. Suspect the ESC or ECM. What might be the problem?
Jul 22, 2019 at 11:55 AM
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ASEMASTER6371
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Good afternoon,

What was the compression?

If you installed a new distributor and have no spark to 1 cylinder, then something is wrong with the distributor. What kind and where did you buy it?

The ECM has no involvement in spark to number 8.

Roy
Jul 22, 2019 at 12:32 PM
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GLIDERBOY19
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Bought the new distributor at O'Rielly auto. The old one did the same thing.
Jul 22, 2019 at 1:01 PM
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ASEMASTER6371
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Did you set the plug on the manifold to be sure there is no spark?

It does not make sense for not having spark on 1 cylinder with all the resr firing.

Is the wire grounding anywhere?

Roy
Jul 22, 2019 at 1:05 PM
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GLIDERBOY19
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Compression on #8 was 150lbs. This engine has 92,000 miles on it. The problem began as intermittent.
Jul 22, 2019 at 1:05 PM
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GLIDERBOY19
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Tied the test plug to a good ground. Got the same response.
Jul 22, 2019 at 1:07 PM
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ASEMASTER6371
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Did you change the cap and rotor?

Roy
Jul 22, 2019 at 1:11 PM
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GLIDERBOY19
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Yes. Changed the rotor and cap. Also new distributor module.
Jul 22, 2019 at 1:21 PM
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ASEMASTER6371
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A new module should have come with the distributor.

None of this makes any sense. You have changed all the components with no result in spark for 1 cylinder.

Does the shaft in the distributor have any lateral play?

Roy

Jul 22, 2019 at 1:24 PM
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GLIDERBOY19
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No.
Jul 22, 2019 at 1:30 PM
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ASEMASTER6371
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Okay, something was missed somewhere.

Start over and recheck everything. Check the wire with an ohmmeter and tell me the resistance.

Roy
Jul 22, 2019 at 1:34 PM