hard start when raining?? or wet

[98 accent hb]

we have been getting lots of rain and it seems to not start up right away like it usually does. has new plugs and wires but some faulty 02 sensors and right before the one near the cat i have a small hole in my flex coupling. any ideas?? i check the battery....good
i checked the alternater......good
doesnt sound like the starter (no ticking or clicking)

[Uncle Eli]

Sounds like an hairline crack in your coil, spray some silicone on your coil to seal the crack