93 5.0 Knock when cold
 

Curiosity here.

When the truck decides to start since cleveland ohio is currently in worse shape then alaska.... The truck has a major knock while its cold and won't idle to save its life. Once its warm the knock disappears (noticeably at least, not 100% sure) and it will idle no problem. Any ideas as to what it can be?

If its possible, can you send me to links where i can read and follow directions on how to do whatever suggested to fix? Thanks everyone!