Stevens, Davis, Miller & Mosher
Run on prevention system supplying maximum exhaust gas recirculation
 An internal combustion engine includes an intake system and an exhaaust system, and an exhaust gas recirculation conduit leads from the exhaust system to the intake system for recirculating exhaust gas. An exhaust gas recirculation control valve at an intermediate part of the exhaust gas recirculation passage controls the flow of exhaust gases therein, and is operated by supply of actuating vacuum. The supply of actuating vacuum to the exhaust gas recirculation control valve is furnished according to engine operational conditions. A vacuum tank accumulates vacuum while the engine is running. A vacuum conduit joins the vacuum tank to the exhaust gas recirculation control valve, and is controlled by a vacuum valve which is closed when the ignition system of the engine is being supplied with electrical power, and is open when the ignition system is not being supplied with electrical power. When the engine is switched off, the vacuum valve opens and supplies vacuum from the vacuum tank to operate the exhaust gas recirculation control valve and to open the exhaust gas recirculation valve to its maximum extent, thus providing maximum exhaust gas recirculation, in order to prevent run on of the internal combustion engine in dieseling fashion. 
Toyota Jidosha Kogyo Kabushiki Kaisha
F F Y
F02B F02M Y10S
additional inventional additional
Takeo Takanori Akira
Miyoshi Nagai Ii