Lordstown Motors Corp. on Thursday said Daniel Ninivaggi, a longtime automotive-industry executive and lieutenant to billionaire Carl Icahn, has joined the electric-truck startup as chief executive and a member of the board.

Mr. Ninivaggi once served as CEO of Icahn Enterprises LP and ran Icahn’s automotive aftermarket service network and parts distribution businesses. He also served as co-chairman and co-CEO of Icahn’s Federal Mogul unit before its sale to Tenneco Inc.

Lordstown, which plans to build electric pickup trucks at a former General Motors Co. assembly plant in Ohio, in June said Steve Burns, its former CEO, had resigned, along with finance chief Julio Rodriguez, after a report from a board committee found inaccuracies in parts of the company’s disclosures on truck preorders.

The company recently disclosed that the Securities and Exchange Commission and the Justice Department are investigating aspects of its business.

Mr. Ninivaggi, 57 years old, serves as chairman of Garrett Motion Inc. Lordstown said Mr. Ninivaggi will receive an annual salary of $750,000 and an annual bonus with a target of 125% of his base pay.

The company said Angela Strand, who has been serving as executive chairwoman, will continue as nonexecutive chairwoman.

Shares were up 5.4% at $5.81 in premarket trading.

Lucid, Fisker, Rivian and Canoo are among the well-funded startups racing to release new electric vehicles. WSJ asked CEOs and industry insiders how new auto companies plan to challenge Tesla’s market dominance and take on legacy car makers. Photo composite: George Downs The Wall Street Journal Interactive Edition