Gator Girl

I need help!!! 2001, , manual tranny, 166,000 miles on it. It was running rough so we hooked it up to a code reader and misfire cylinder 3 came back, intermittently- it runs smooth as silk until there is a load on the engine. Over the past two weeks we have changes plugs (twice), ignition coils (twice), a cam sensor and the computer. The original computer still has the misfire intermittently, the second computer came back with the cam sensor issue and still reads a code on there even after we changed the part (a new part). What on EARTH is left? We have compression in the cylinder, when we unplug the wire from the coil there is a significant difference. We are going to check the voltage going to the coil but ANY ideas would be appreciated!!!!!