DETROIT -

General Motors says it will invest $385 million at an engine plant near Detroit, creating or keeping 320 jobs.

The company says the Romulus engine plant west of Detroit will build a new fuel-efficient motor.

General Motors Co. is not providing any details about the new engine. The company also won't say how many of the 320 jobs are new.

The Romulus plant now has 840 workers on two shifts. It makes V-6 and V-8 engines for pickup trucks, full-sized vans and sport utility vehicles. The engines also have boating and industrial uses.

GM said Monday that the investment will pay for new equipment and upgrades.