Diagnosing leak----only leaks when water is used

[shooteneq1]

I am praying somebody can help me out here or give me an idea of what i got going on. i have a leak in my kitchen coming from somewhere behind my sink but i cant figure out where and its doing thing i wouldnt expect from a leak. I keep getting water flowing into the area where my dishwasher is, it is currently removed and not hooked up. i know the drain to the sink is not leaking as i have dumped gallons of water into it without the sink running and it stays dry.

The hot and cold water shutoff valves are exposed below the sink and stay dry no matter what. i am assuming the leak has got to be coming from inside the wall. What i dont understand is the pipe in the wall is behind the shutoff valve so it would always be pressurized and should be leaking 24/7 however it only leaks when the water is turned on. It defies logic to me but i dont know all the ins and outs to plumbing. I have alot of construction experience but before i rip my cabinets apart and potentially the block walls i was hoping i could get some insight to this problem. Any help is appreciated

Thanks, Kristian

 

[frodo]

have you checked the sprayer? it could be leaking only when used

is the faucet sealed to the sink?

is sink sealed to counter top?

do you have aav?

outside faucet?

leaking clean out plug

post pictures of the area, maybe we can see something

 

[shooteneq1]

The leak has to be coming from in the wall. Everything in the sink area is dry, i laid cardboard down as well and theres nothing in the area, i did demo to where the pipe comes out of the wall and its dry there as well so it has to be somewhere farther back inside. I just dont understand why it would leak only when water is being used and not all the time.

 

[shooteneq1]

here is where the cold water pipe comes out the wall, the hot water looks the same

 

[frodo]

block wall. bummer.

is this an outside wall?

go outside, and chip the wall. instead of tearing out cabinets

 

[johnjh2o]

What are the waste lines in the wall and how old are they? I have seen many copper waste lines fail.

 

[shooteneq1]

Its an outer wall, however full brick exterior house. couldnt get much worse, plaster wall, block wall, brick exterior lol. waste line is galvanized 2" pipe. however i dumped lots of water into the sink without turning the water on, 5g buckets with food dye in them, and i had no leaks doing it.

 

[shooteneq1]

my cabinets are going to need to be replaced eventually, theres mold 4" up them when you look on the sides.

 

[SHR]

Your drain line is leaking somewhere. Open wall and expose entire drain line. You have to open the wall to remediate the mold anyway.

 

[Mr_David]

back up and take a few more photos of the sink, faucet and the entire cabinet below. maybe some here will spot something. Seems like you were thorough in you investigation. more picture may help