Test methods for individual coil packs
Can anyone describe some ways to test individual coil packs?
I was getting a misfire on cylinder 4. I looked at the spark plugs and they looked like they hadn't ever been changed (179000 miles later)! Gap was around 0.065-0.080", and very corroded plugs. The plug in cylinder 4 and 6 had a little oil on the threads, so I tightened the valve cover bolts, hoping that'll take care of it. Also, the boot had a little what looked like burnt oil going up the side, and the spring inside had some brown goop on it. After changing the front 3 easy plugs, boots and springs, engine runs much better but still has a couple hick-ups at idle from time to time. I'm going to pull the intake manifold off and replace the back 3 plugs also, and while I've got it apart I'd like to check the coil packs. I've got a multimeter, but I'm new to it, and don't know much about ohm testing.
Thanks for the help!
2000 Ford Taurus Sedan
3.0L Duratec DOHC