I'd like to know the answer to that as well. I have a 2002 Taurus with the 3.0L OHV. I am getting an intermittent miss and once had a pending code for a misfire on cylinder 3. The secondary resistance is out of spec acccording to my Haynes manual.Can a coil whose windings (both primary & secondary) repeatedly pass a resistance check still be capable of flaking out, particularly when the engine is under load? This coil passes visual inspection as well.
Application: '91 Sable 3.8L
The secondary resistnance is out of spec at the coil. Haynes says it should be 13600 ohms across each coil and I measured 11800 ohms. No range is given so I don't know if that's acceptable or not. I notice the miss starts when the engine is warm and the RPM's are low (in overdrive) and the engine is under a little load.Goathead: what is your original problem? The coil could still be weak under load, with higher rpm's. Is there a spark leak anywhere?
jaba: What secondary resistance is too high? At the coil, or plug wire?