The BMW i3 electric car is a tour de force of advanced engineering--and it was the most energy-efficient car sold in the U.S. in 2014 and 2015.

Its body shell is made of carbon-fiber reinforced plastic, riding on an aluminum platform containing the lithium-ion battery, the electric motor, and the crash structures.

But you can't get AM radio in the car. In other words, no local traffic reports or news headlines for you, harried commuter.

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We noticed this quirk in the BMW i3 REx extended-range electric cars tested over by several High Gear Media editors. We've now driven numerous European vehicles without AM reception.

As devotees of New York City's 50-year-old 1010WINS--with its traffic updates "every 10 minutes on the ones"--we wondered why the car didn't include AM reception.

[EDITOR'S NOTE: We first published this story in June 2015. More than two years later, we may have a partial explanation to the question posed in the title. It turns out that several European countries are in the process of ending analog radio broadcasts altogether, replacing them with digital audio. Norway will turn off FM radio this year. In the U.S., fewer than one in five people now listen to AM radio, while use of satellite and Internet radio has risen rapidly. Perhaps BMW simply anticipated its inevitable decline, choosing not to make the effort to protect its audio system against interference with analog reception?]

2015 BMW i3 REx - Driven, Portland OR, April 2015

2015 BMW i3 REx - Driven, Portland OR, April 2015

"AM is not offered due to negative performance influences of the electromagnetic interference of the electric drivetrain," said Rebecca K. Kiehne, a BMW product and technical communications spokesperson.

"Electric motors cause interference on AM which is why BMW decided to remove this option.

"While it could be offered, BMW's performance standards are very high and we don't offer a product that meets less than those high standards."

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This puzzled us, since virtually every other electric or hybrid car on the market manages to include AM radio without trouble.

We asked Kiehne for more details, but didn't get specific answers on why the interference would be comparatively greater in the BMW i3 than in any other vehicle with an electric traction motor.

We surmise it could have something to do with the CFRP body shell, but Kiehne wasn't terribly forthcoming.

2015 BMW i3 REx - Driven, Portland OR, April 2015

2015 BMW i3 REx - Driven, Portland OR, April 2015

BMW's two prior electric-car test fleets managed to incorporate AM radio: It was a standard fitting in both the MINI E and the BMW ActiveE.

"It wasn't great," said one driver familiar with all three cars, "but it wasn't terrible either."

Even stranger, it turns out the BMW i3 does have AM radio built in--but BMW has disabled it.

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"Depending on where you live," an i3 owner told us, "the reception can be very bad due to interference from the electric drive electronics."

"From what I got out of BMW, the interference was unacceptable for them and they felt their customers would be complaining about it," he said.

But those customers would "bring the cars to the dealers, and the dealers wouldn't be able to do anything."

2015 BMW i3 REx - Driven, Portland OR, April 2015

2015 BMW i3 REx - Driven, Portland OR, April 2015

So the BMW i3 offers energy efficiency, power, and its unique optional range-extending two-cylinder engine—but not AM radio.

Some owners, we later learned, have gone in and modified the software in their cars, known as "coding" the i3 (which we suspect may void some or all of the warranty).

Those owners said the AM radio largely works fine. Some report minor interference, but most say it's perfectly acceptable.

With web-connected 4G mobile devices and live traffic data integrated into the i3's navigation system, perhaps AM radio is now simply a relic of the past that drivers can do without--rather like CD players?

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