Originally posted by stuvx:
Wouldn't a power balance test tell you exactly which cylinder(s) is misfiring? Then once you know the cylinder(s), you can narrow your testing to determine whether it's a fuel, compression, or spark issue.

You can do this test with a few lengths of electrical wire, a tachometer, and a grounded screw driver. You can probably find a tutorial on the web in case no one has written one in this forum.



On an older car, yes, however, this Contour uses a coil for a pair of cylinders. Suspect in this case is the coil for cylinders 2 and 6, which fire at the same time. One cylinder will be on the power stroke, the other will be on the exhaust stroke (to burn any remaining unburned fuel) if I remember correctly. So, if you ground out that coil (which I don't recommend on computerized cars and transistor ignition) you still won't know which cylinder is misfiring, 2 or 6.

Depending on the year of the car, a high-end scan tool may have the capability to turn off one injector at a time. If the problem is truly injector #6, and it is easy to duplicate the misfire condition, this feature could certainly help out there. An up-to-date OTC Genisys scan tool has this ability, at least for a 1998 Taurus SHO.

-Rod