Abstract: Disclosed is a system for removing particulates from the exhaust gas of a vehicle internal combustion engine during those times that the emission of such particulates into the atmosphere would be of greatest danger to persons in the vicinity of the vehicle. The system comprises valve means connected to the vehicle exhaust manifold for normally directing exhaust to the atmosphere when in the nonactivated condition. The valve means directs exhaust to a particulate filter when in the activated condition. Means responsive to the starting of the engine activates the valve means for a predetermined period of time. The valve means can also be activated by shifting into reverse gear.