The answer to 'GFCI outlet sparking' is that a sparking GFCI outlet is a sign of an electrical issue that should be addressed promptly. Common causes include a faulty GFCI, a short circuit in the wiring, or moisture intrusion. Symptoms may include the outlet repeatedly tripping, flickering lights, or a burning smell. Solutions can range from resetting the GFCI to replacing the outlet or addressing underlying wiring problems.
If the sparking is intermittent or the outlet continues to trip, it's best to call a licensed electrician to diagnose and repair the issue. Attempting DIY electrical work on a sparking outlet can be dangerous and is generally not recommended for homeowners without proper training and experience.