I have a Moen two handle sink faucet with sprayer. Recently the sprayer has quit working properly. Some of the water continues to run out the faucet when the sprayer button is pushed. I think that this is an indication that a diverter valve is not working as it should. Is this a replaceable item? If so, is this an item available for free from Moen as are the cartridges? I don't know the model #, but it is at least 5 years old. Is the diverter different for various models? Thanks for any advise.