Where is the moisture coming from?

Ford F250 2000. Moisture on ignition module causing miss. Seems to be clear water no coolant. No leak in coolant because level stays the same. Module is rear right looking from grill. No apparent leaks on hood gasket. No AC lines over or near module. Replaced intake manifold 2 times but skip returns sometimes in days, sometimes weeks or months. If you dry the module by removing, blowing water off module and out from around plug miss goes away. Happening more frequently in past 2 months. Have had heavy rains durning the period but no apparent leak to engine compartment.