no spark on passenger side of engine

1999 GMC SIERRA
208,000 MILES
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SHANENEALE
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i have a 1999 gmc seirra 1500 4x4 with the 4.8 in it. i get spark on my driverside but i dont get any spark on my passenger side. i reasontly changed the intake manifold on it i dont know if that would have anything to do with it. i had to take off my wiring harnest to change it but i pluged evry thing back in.
Oct 24, 2013 at 3:13 PM
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SATURNTECH9
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So are you missing the power side to the coil or ground pulse to the coil?
Oct 24, 2013 at 3:37 PM
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SHANENEALE
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No i dident mess with that side of the coil packs when i changed it plus two on that side are brand new
Oct 24, 2013 at 3:51 PM
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SATURNTECH9
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If your not getting spark to any of the cylinders on the passenger side you have to be missing the power and or the ground pulse to the coils?Simple as that have you checked yet?
Oct 24, 2013 at 8:32 PM
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SHANENEALE
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How do you check that
Oct 26, 2013 at 7:13 AM
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SATURNTECH9
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Do you have a test light light or multi meter?
Oct 26, 2013 at 8:16 AM
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SHANENEALE
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Yes
Oct 26, 2013 at 9:44 AM
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SATURNTECH9
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Alright with a test light with the key in the run position pin D on the connector going to the coil should have power to it on all four of the connectors.Also Pin C on the connector should have a flashing ground while cranking. Pin A to the connector should have a constant ground to it.
Oct 26, 2013 at 5:03 PM
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DM AUTO
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No ground pulse.
May 3, 2018 at 4:00 PM
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DM AUTO
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Did your test everything but ground pulsing?
May 3, 2018 at 4:00 PM
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STRAILER
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This sounds like you lost the coil drivers inside the PCM which means it needs to be replaced. Here is the location.

You may be able to get a used one and plug it in to confirm the issue.

Check out the diagrams (below).

Please let us know what you find. We are interested to see what it is.

Cheers, Ken
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May 6, 2018 at 4:38 PM