My Moen kitchen faucet stopped working suddenly in that only a thin stream of water would flow at most when I turned on the hot water handle or the cold water handle to the maximum positions. I replaced the faucet with a new facet and all is working fine. My Moen faucet was only 2 years old. Has anyone seen such a problem please? I'm thinking it's a mechanical problem in the faucet.

there is a diverter inside the faucet that works with water pressure possibly has some debris or calcium build up.turn off water supply and take out cartridge. you should see the diverter

take the handle off the hot water side. unscrew the cartridge and check for sediment.

The cartridge is defective, contact Moen for replacement part

Not sure whether you are aware or not but most times, if you call moen with your model number and explain the problem your having, they will usually send you (free of charge-lifetime warranty) the part with instructions on repairing it along with it. You may have the 7800 series, but there are 3 or 4 different models if you check their site, and can identify the actual model, they will send you repair parts. Tell them you bought it ? years ago, and don't have the receipt, if they even ask.
try this link, if no luck, get back to me.
http://www.moen.com/replacement-parts

Rubber gasket on the water shut off valve under the sink has come off and traveled up into the faucet. It's pretty difficult to get it out. If you have access to an air compressor you may get lucky by taking the faucet completely off the sink and blowing air back from the faucet outlet back into the internal piping to dislodge the rubber piece. If that doesn't work, or you can't use the air compressor method, then it's a trip to the hardware store for a new faucet.

Hot water line connected to left side of faucet? Did you replace tap set, or just cartridge? Cartridge may be out 180 degrees.

There is a small diverter valve on the faucet underneath where the hose connects too it needs to be replaced depending on the age of the faucet I usually recommend replacing the entire faucet with another Moen product

I have moen kitchen faucet # 7560 and water pressure very low. What should I do? We check water flow in pipe it is ok. I changed cartridge as well as pipe nothing help. Please let me know. thanks

your problem can be fixed by running a loop in the plumbing. If you hired a professional in the first place it would already be done. basically the water pressure isn't enough, i bet your faucet is on the second or third floor, or even just THAT far from the water heater.

Just need to replace the cartridge. It happens....might be fun trying to get that one out though with the way it stopped working.