Just last week, I discovered that water is no longer running through my kitchen faucet when I turn the faucet on (neither cold nor hot). However, water will run through the spray when I turn the spray on (responding to both cold and hot directions). The faucet is a single handle faucet. I can't seem to troubleshoot this problem. Does anyone have any possible root causes for this occurrence? Thanks.

I could answer better if I knew the brand name of your faucet so I could instruct you how to open it up but I believe I know what's happened. First off I want you to unscrew the aerator from the spout and turn the water back on. Do you have a stream? If so clean the aerator screens. If not get back to me. Regards, Tom