Smoking Vehicles

DEP regulations stipulate that a motor vehicle shall not emit visible smoke, whether from crankcase emissions or from tailpipe exhaust, for a period in excess of three consecutive seconds. Smoke, in this context, means unburned particles resulting from incomplete combustion. Smoke does not refer to visible water vapor often emitted when starting a vehicle on a cold day. Engines emitting black smoke likely have an overly rich fuel mixture or a malfunction resulting in incomplete combustion of the fuel. Engines emitting white or gray smoke may be burning antifreeze leaking into the combustion chambers from a cracked cylinder head or block. Engines emitting bluish smoke are likely burning oil, which could be the result of various engine problems.

To Report Idling or Smoking Vehicles:

Call the DEP 24-hour, toll-free hotline at (877) 927-6337 or (877) WARN DEP or your local police department (please do not call 911).

Additionally, Warn DEP now has a mobile App.

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