Production of a vehicle critical to the future of electric carmaker Tesla is lagging badly due in large part to problems at the company’s Nevada battery factory.

During a Wednesday call with investors CEO Elon Musk described a breakdown that’s essentially disabled half of the production zones for critical battery modules.

“The primary construction constraint by far is in battery module assembly,” said Musk. “Zones three and four are in good shape, zones one and two are not.”

Musk blamed a subcontractor for the failures he said didn’t come to light until recently. As a result, according to Musk, the company’s executives and teams of engineers are virtually living at the factory.

“I move myself to wherever the biggest problem is for Tesla,” said Musk. “I really believe one should lead from the front lines that is why I’m here.”

Musk said the Model 3 production rate could reach 5,000 per week by the end of the first quarter of 2018, roughly three months behind prior estimates.

Musk, who earlier this week posted images on Instagram from a campfire gathering on the Gigafactory roof, described myriad problems with software, electronics and mechanical parts.

“We did not realize the degree to which the ball was dropped until quite recently,” Musk said. “We had to rewrite all of the software from scratch and redo many of the mechanical and electrical elements of zone two.”

Although the factory problems were enough to delay Model 3 production for months, Musk said the operation will rebound.

“We are very confident about our future,” he said. “This will not be a constraint in the future.”

Located east of Sparks in the Tahoe-Reno Industrial Center the Gigafactory is a joint project between Tesla and Panasonic.

The factory, which Musk once estimated would cost about $5 billion to build, is operational but not yet completed. Competition from state and local governments to host the factory was fierce. The Nevada Legislature and Gov. Brian Sandoval authorized a tax package worth $1.3 billion over 20 years in order to convince Tesla to build in the state.

Tesla acknowledged Wednesday that it would not achieve its previous goal of hitting a production rate of 5,000 Model 3 vehicles per week by the end of the year, instead pledging to do so by the "late" first quarter "based on what we know now."

With delays stacking up, the company swung from a $22 million profit in 2016's third quarter to a net loss of $619 million, much worse than S&P Global Market Intelligence's projection of $498 million.

The wait for a Model 3 was already quite long, compared with auto industry standards. With several hundred thousand people placing refundable deposits for the vehicle, anyone who orders a car now is unlikely to receive it until at least 2019, and possibly later.

The company also appeared to back off Musk's previous pledge to hit a production rate of 10,000 weekly vehicles sometime in 2018, saying in a letter to investors that would come sometime after the 5,000 benchmark is achieved.

Tesla will also make 10 percent fewer units of the Model S sedan and Model X crossover in the fourth quarter to reallocate manufacturing resources to the sputtering Model 3.

Still, the company said the Model 3 would overcome those challenges and hit a breakeven point in gross profit margin by the fourth quarter of 2018.

Musk also defended the company's recent firing of hundreds of workers at its Fremont, Calif., headquarters and factory following performance reviews, blasting reporters who suggested it was an unusual review and comparing the move to General Electric's famous annual decision to remove low performers.

The company, he said, has high standards.

"If they are not high, we will die," he said. And reporters who breathlessly wrote about the firings "should be ashamed of themselves for lacking journalistic integrity."

Also Wednesday, Tesla reported third-quarter revenue of $2.98 billion, up 29.9% from a year earlier. That edged S&P Global Market Intelligence expectations of $2.94 billion.

Tesla's stock fell 3.6% to $309.64 after the bell.

USA TODAY reporter Nathan Bomey contributed to this report