Ive been chasing some random misfires in two cylinders (5 and 6). I've done all the typical troubleshooting like swapping coils, checking the plugs for soot/fuel/soot, checked wires and even conducted compression checks (150 psi). I solved the #6 issue after swapping the coils but everything on #5 failed to isolate the cause.

I did notice that when hooked up the scanner the misfire literally counts from 1 to 190, resets and starts all over again. It even does this when plug wire is disconnected. I also noticed that when the #5 plug wire or injector is disconnected there is no difference in the way the engine runs. It actually seems to rev a little smoother as well but that could be my imagination.

I'll pop the valve cover tomorrow to see if something happened to the springs but i just had the cover off last moth and noticed nothing wrong.