Low end knock and failed inspection?
 

I keep trying to get my 02 LS1 to pass inspection, and one of the last and latest problems is that my #7 cylinder is showing a miss, then it shows as a dead cylinder. Shortly after that a low pitched 'knock' type sound and then i failed on the code for the knock sensor and my timing started retarding. I've changed plugs, wires, and fixed probably 9 different codes but the P0307 for #7 miss or dead always shows up. Question is...if that cylinder IS dead for reasons say...coil pac or injector can it create that sound and set off the knock sensor? Cause i was told the sensor is retarding my timing and the more it does the more i can hear the noise. Or should i be looking for rods, journals, main bearings....leuprechauns?