Tesla Inc., Ford Motor Co. and General Motors Co. will report record electric-vehicle salesfor September as consumers rushed to take advantage of expiring federal-tax incentives. 
As the sales spikegives way to sagging demand, the automakers face questions on how they plan to navigate shifting US policy on plug-in vehicles. Already, GM has flagged a $1.6 billion charge for adjusting production in response to government levy and incentive changes.
The companies’ ongoing efforts to expand domestic production, spurred by tariffs on imports of vehicles and auto parts, have an added urgency following China’s move to restrict ...