It Looks Like A Single Tweet From Elon Musk Boosted Tesla By 5%

Tesla closed on Thursday up 5%, at $251. Shares had spent the week sliding.

Then CEO Elon Musk tweeted on Wednesday night about some called "D" (probably the all-wheel-drive version of the company's Model S sedan). Whatever it is, it will be unveiled on Oct. 9, along with "something else," Musk said.

You could argue that Musk set off Tesla's decline with his own comments about the stock being overvalued. And with one tweet and a photo, he appears to have stopped the bleeding.