| 123 / | HD | INTERNAL-COMBUSTION ENGINES | 
| 434 | DF | CHARGE FORMING DEVICE (E.G., POLLUTION CONTROL) {29} | 
| 672 | DF | .~ Including exhaust gas condition responsive means {11} | 
| 679 | DF | .~.~ Combined with engine condition responsive means {6} | 
| 681 | DF | .~.~.~ Engine load responsive {3} | 
| 682 |  | .~.~.~.~ Acceleration or deceleration responsive |