2007 Silverado problem...
 

I started having a flashing check engine light on my 2007 Silverado with a 5.3 L engine. The code was for a misfire on cylinder 4. I replaced plugs, plug wires for all 8 cylinders and the coil pack on cylinder 4. Now the truck will not start. I just hear a loud click... I tightened the battery cables, tried to jump it, still just a click... Any thoughts?

I would check both battery cables at both ends for looseness and corrosion. I would also have the battery checked. Jumping a vehicle doesn't always work due to several factors such as bad connections of the jumper cables, poor quality jumper cables and if the problem is with your battery cables, the jumper cables won't work.

After you get done confirming good connections from the battery to the vehicle, sometimes if the brushes in the starter or the contacts inside the solenoid are dirty or worn, a rap or two to the starter may allow contact for one or two more starts. If that allows it to start, plan on replacing the starter assy, usually with a rebuilt exchange starter.