Originally Posted by The Fixer
Go get yourself a new rear hub, PRONTO! You don't wanna be hammering out of the saddle when that happens.... your balls will suffer..
Best advice in this whole thread (but there's very little competition for that honour).
It's bike shop time... clearly the original poster doesn't have the skills (and I'll bet the tools) to open up a freehub/freewheel. Likely the part will be replaced as the labour charge to open/repair/rebuild a freehub/freewheel can be high.
Oh... and "been there, done that"... I had a malfunctioning Dura-Ace (of all things) freehub let go in a sprint. The crash was painful.