On first glance, the mid-November traffic on Nashville’s Interstate 24 looked like any other morning rush hour—too many cars packed onto a roadway at one time. But if you could access data inside every car, you’d notice that some weren’t speeding up and slowing down as aggressively as the rest…

The 100 “influencer” vehicles on the interstate were part of a test by CIRCLES, a consortium of universities, government and automakers like Nissan, GM and Toyota aiming to pair existing cruise control technology with A.I. and auto data connections to reduce the instabilities in traffic flow, known as “phantom jams,” that cause all sorts of problems on the road…

Once the Tennessee data is crunched over the coming months, Alexandre Bayen, the UC Berkeley professor of electrical engineering and computer science who is leading the effort, expects it to show that introducing even a small number of connected, A.I.-powered vehicles—less than 5% of the total—to the traffic flow will cut energy consumption by 10%.