One highly particularized automotive subculture for diesel pickup trucks has produced the phenomenon of “rolling coal” or “coal rolling.” For the uninitiated, diesel truck owners modify their on-board computers and exhaust systems to cause the vehicle to run an ultra-rich fuel-to-air mixture (i.e. feeding more diesel fuel into the engine than normal). The result is a thick belching of dark black smoke from the exhaust pipes – often directed at hybrid- and electric-powered cars.
The State of New Jersey, through Gov. Chris Christie’s signature, has just enacted a ban on this exact modification of diesel trucks. This sounds like a win for champions of breathing clean air – even if NJ and the EPA already have a ban for such behavior (Don’t you just love lawmakers?).
Will North Carolina follow suit in enacting similar legislature? One could argue that the state has already outlawed this behavior:
NCGS § 20-128.1(a)(2) makes it an infraction “For any diesel-powered motor vehicle registered and operated in this State to emit for longer than five consecutive seconds under any mode of operation visible air contaminants which are equal to or darker than the shade or density designated as No. 1 on the Ringelmann Chart or are equal to or darker than a shade or density of twenty percent (20%) opacity.”
NCGS § 20‑136 makes it a Class I Felony to “drive, operate, equip or be in the possession of any automobile or other motor vehicle containing, or in any manner provided with, a mechanical machine or device designed, used or capable of being used for the purpose of discharging, creating or causing, in any manner, to be discharged or emitted, either from itself or from the automobile or other motor vehicle to which attached, any unusual amount of smoke, gas or other substance not necessary to the actual propulsion, care and keep of said vehicle…”
This sounds like to me purely an enforcement issue. More than likely a police officer would need to witness an instance of “rolling coal” to cite/arrest an offending individual. But, as these modifications can typically be disabled via a switch in the cab of the truck, police will have trouble catching a coal-roller in the act.