Over the past few years, some of America's, shall we say, less enlightened drivers hit upon a new trend.

They started modifying big diesel trucks to spew clouds of soot and smoke whenever the driver hit the accelerator.

It's called "rolling coal"--and drivers of hybrid and electric cars report that it often seemed to be directed at them.

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Not that it's not obnoxious to anyone caught in the clouds of black soot and uncombusted diesel fuel spewing from the gigantic tailpipes of the modified trucks.

Diesel trade groups have denounced the practice in the strongest possible terms, since it ruins the public image of "clean diesel" they're trying to inculcate.

While the practice is theoretically illegal, thanks to Federal emissions standards, Illinois politicians are now targeting coal-rollers specifically.

Pickup truck

Pickup truck

A bill calling for a $5,000 fine for rolling coal was recently introduced to the Illinois General Assembly by Representative Will Guzzardi, reports AutoGuide.

The bill would amend a current law that already prohibits any modifications to diesel vehicles that tamper with pollution-control equipment.

The law already states that no person shall modify a vehicle with the intention of increasing its capacity to "emit soot, smoke, or other particulate emissions."

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The proposed fine would essentially help enforce this existing rule.

Doing that should already be illegal under the Federal Clean Air Act. That's because it typically involves removing mandatory emissions-control equipment, or making other changes to deliberately increase the level of pollutants in the exhaust.

However, these regulations don't apply to heavy-duty trucks that weigh more than 6,000 pounds.

2013 Ram 2500 HD

2013 Ram 2500 HD

Those vehicles--including heavy-duty versions of the Ford F-Series, Chevrolet Silverado, and Ram pickup--are often the ones used for rolling coal.

This isn't the first time a state legislature has tried to craft regulations that eliminate any ambiguity in the matter.

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Last year, New Jersey Assemblyman Tim Eustace introduced an anti-rolling-coal bill after experiencing it himself.

While driving a Nissan Leaf electric car, he was engulfed in a cloud of smoke produced by a large pickup truck that rolled alongside him.


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