Engine will not crank, no spark or fuel pump after engine swap?

2003 GMC SIERRA
100,000 MILES • 5.3L
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JOHN'S HEADACHE
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  • 1 POST
Just removed blown up 6.0l ls and replaced with a 5.3l ls from a 2007 Chevrolet Tahoe now engine wont crank, no spark or fuel pump. Used the original harness and computer.
May 2, 2023 at 11:01 AM
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STRAILER
  • ✓Experienced Mechanic
  • 55,249 POSTS
Please double check the main engine ground to the wiring harness, here is the location so you can see what I am talking about. Check out the images (below). Let us know what happens and please upload pictures or videos of the problem so we can see what's going on.
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May 3, 2023 at 3:16 AM
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