Moen kitchen faucet set wsprayer can't shut sprayer.

Moen Spray Diverter Repair
First, remove head and soak in vinegar. Use toothbrush to remove scale. If this fixes your problem, ignore the following.

To repair your Moen sprayer, first pick up Moen part # 91192 diverter and a Moen #117 spout o-ring set. Remove the cap on handle, remove the screw on the interior cap and remove handle. Your spout can now be removed by pulling it straight up. Here is a pic of the part. Slide the diverter up and off the faucet post. Remove the two o-rings from the post and install only one large one and one small one onto post making sure to grease them with the silicone provided. The other small o-ring is for faucets without the spray. Discard it. Slide the new diverter down onto the post and reassemble the spout and handle assemblies. Make sure to properly engage the flat on the handle into the groove on the retainer nut when reinstalling handle..
Good luck!

If it is simply clogged, soak the head in vinegar for an hour and use a brush to clean the scale from the spray head.

Instructions if your sprayer has failed:
To repair your moen sprayer, first pick up Moen part # 91192 diverter and a Moen #117 spout o-ring set. Remove the cap on handle, remove the screw on the interior cap and remove handle. Your spout can now be removed by pulling it straight up. Here is a pic of the part. Slide the diverter up and off the faucet post. Remove the two o-rings from the post and install only one large one and one small one onto post making sure to grease them with the silicone provided.The other small oring is for faucets without the spray. Discard it. Slide the new divertor down onto the post and reassemble the spout and handle assemblies. Make sure to properly engage the flat on the handle into the groove on the retainer nut when reinstalling.
Good luck!

Moen has a diverter built in that will need to be replaced.

use the same steps as when you replaced the cartridge, but this time you will need to remove the spout, there is a small diverter, you will see it when spout is removed.

take this part with you to the hardware store, along with the O Rings from the spout, as they will need to be replaced also

use a non silicone faucet lubricant when putting back together

probably hard water build up.I used a tooth pick inserted into each little hole to dislodge the build up

We had this same problem. We twisted off the sprayer cap to access the diverter valve under the trigger. The nylon diverter was stuck down into the cavity and was not popping out when the trigger was released. We pushed it down several times with needle nosed pliers to release it then applied a drop of household oil lubricant with the valve pushed all the way in. Then pushed and released several times to work the lubricant around the sides of the valve. After re-assembly, the sprayer seems to work perfectly again.

This might mean that the diverter in that controls the sprayer needs replacing. It is located behind the valve body underneath the tub spout sleeving

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

Call Moen. Bad spray head or diverter.

Turn it the opposite way. They are made to go on just the opposite of what you think you would do to turn them

call moen for new cartridge