When I opened my outdoor spigot/faucet after the winter it was leaking. It doesn't leak when I don't have it on. There is the knob to turn on the water and right behind it is a gray cap. 1/2 of the water comes out of there and 1/2 out of the part it's suppose to come out of. Not sure what the gray cap is for? Is it something we can fix ourselves or should we call a plumber (trying to avoid this)?
Thanks

The gray cap is an air breaker to stop back siphoning. It looks like you have a bad check valve which might be repairable. Any chance of a picture? Try unscrewing the cap counterclockwise.

Sounds like the vacuum breaker (that gray cap) froze and burst. You may be able to purchase the same model of outside faucet and steal the parts from that one to replace the defective one WITHOUT HAVING TO REMOVE THE OLD VALVE. May even be able to purchase a replacement vacuum breaker... but don't get your hopes up on that.

Check your local home supply stores.. see if they have repair parts or an exact match on your valve (about $25.00).

If no replacements or parts available, most likely will need to replace that outside faucet to a new one.

Let us know how it goes... Mark

If this helped, please RATE THIS ANSWER. Thank you.

Any chance you left the hose attached to the spigot this winter? That vac breaker should not have had anything in it to freeze but I think Mark has pegged the problem.