No injector pulse

1994 GMC SIERRA
169,000 MILES • 5.7L • V8 • 4WD • AUTOMATIC
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CARSDAVE84
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No fuel being delivered to cylinders. Fuel system including throttle body has been replaced, noid light is not showing any pulse. Ignition module has been replaced as well. I am wondering what else I can check for. Fuses and relays are good as well.
Sep 24, 2018 at 1:38 PM
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ASEMASTER6371
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Good afternoon.

Do you have spark? For the injectors to fire, the ECM needs to see a crank signal or rpm reading.

Do you have power to the injectors? Fuse box feeds power to the injectors and the ECM quad drives ground the injector for fuel to flow.

I attached a diagram for you to view. Check the fuse listed for power on both sides.

Roy
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Sep 24, 2018 at 2:16 PM
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CARSDAVE84
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Thank you for the response. I checked the connections and fuse link with volt meter, I am getting good power on both sides. However, I am not getting spark as well.
Sep 24, 2018 at 4:27 PM
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ASEMASTER6371
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Okay, check the cap and rotor. Check you ignition module as well. Common failure for no spark.

Once you get spark, fuel should return.

Roy

https://www.2carpros.com/articles/how-to-test-an-ignition-system
Sep 24, 2018 at 4:33 PM