Tesla Inc. still hasn't figured out how to overcome manufacturing challenges that threaten its viability as an automaker, with glitches on the battery line pushing out production targets for the Model 3 sedan.

The company won't make 5,000 units per week of its cheapest car until sometime in March, three months later than planned.

"I have to tell you I was really depressed about three or four weeks ago," Chief Executive Officer Elon Musk said on a call with analysts Wednesday after Tesla reported a record quarterly loss and cash burn.