Customer called us out because he had water underneath his kitchen sink. When I arrived I ran the faucet for several minutes and did not see any water leaking from anywhere. I filled the sink up and inspected the drains but did not see any water. I ran the garbage disposal and again, no water leak. After approximately 15 minutes no water leaks appeared. I cut the backboard out and drywall to inspect inside the wall. Everything in the was was dry as well. Finally we discovered that the leak was coming from the kitchen faucet sprayer. It would only leak if you moved the faucet head . If it was stationary nothing would happen. I tighten it down and explained to the customer that he might need to replace the faucet or call the manufacturer to get a new faucet or repair parts. He will monitor the faucet and call us back if he sees any water leaks.