[Themikebleil]

I recently replaced the 4.8 L motor in my 2004 silverado with a 5.3L 2000 motor amd the truck will not spark. I've got gas pressure, my spark plugs, leads and coil packs are all good but for some reason I can't get a spark. I've checked the crank shaft sensor, replaced the map sensor, scanned it with a scan tool and received no error messages. When I put the new motor in I swapped the intakes and wiring harness. Any help would be greatly appreciated

 

[silverado002]

Wow. Lot of work there. Do you have 12V power and good ground to each coil?

 

[RayVoy]

Is the security lamp on by any chance?

 

[Themikebleil]

Is the security lamp on by any chance?

No but after going over it again I found a ground cable that had disconnected in the back

 

[Themikebleil]

Wow. Lot of work there. Do you have 12V power and good ground to each coil?

Thanks for the advice! After combing through again I found a ground cable in the back that had become disconnected and after connecting it she started up just fine