JAW AS 3236093 - Caterpillar

Fuel Injection
The engine ECM controls the timing and the duration of the fuel that is injected. The engine ECM varies the signals to the fuel injectors. Fuel is injected only while an injector solenoid is energized by a 105 volt signal from the engine ECM. The timing of the injection signal determines the engine timing. The length of the injection signal determines engine speed. By controlling the timing and duration of the 105 volt signal, the ECM controls the engine speed.Injection timing depends on the desired engine rpm and on the load. The ECM detects the top center position of each piston. The ECM sends an injection signal at the desired time.Cold Cylinder Cutout
During a cold start or extended periods at low idle, the engine ECM will automatically turn off one unit injector at a time in order to determine if the cylinder is firing. If the ECM determines that the cylinder is not firing, the ECM turns off the unit injector. If the ECM determines that the cylinder is firing, the ECM turns on the unit injector. This strategy improves engine starting. This strategy reduces the following: white smoke, the use of ether injection and warm-up time.Cold Mode Operation
Cold mode controls fuel injection timing when the engine is cold. When the engine is cold, controlling the fuel injection timing reduces the possibility of engine damage. When the engine is cold, controlling the fuel injection timing helps minimize white smoke.Cold mode is activated whenever the engine coolant temperature is below 70 °C (158 °F). Cold mode remains active until the engine coolant temperature is warmer than 73 °C (163 °F).FRC Limit
The flash file inside the engine ECM sets certain limits on the amount of fuel that can be injected. The FRC limit is a limit that is based on the boost pressure. The boost pressure is calculated as the difference in pressure between atmospheric pressure and turbocharger outlet pressure. The FRC limit is used to control the air/fuel ratio for control of emissions. When the engine ECM senses a higher boost pressure, the engine ECM increases the FRC limit. A higher boost pressure indicates that there is more air in the cylinder. When the engine ECM increases the FRC limit, the engine ECM allows more fuel into the cylinder.Rated Fuel Position
The rated fuel position is a limit that is based on the power rating of the engine. The rated fuel position is similar to the rack stops and the torque spring on a mechanically governed engine. The rated fuel position determines maximum power and torque values for a specific engine family and for a specific rating. The rated fuel position is programmed into the flash file at the factory."Multi-Torque" and "Dual Horsepower" Selection (if applicable)
This feature permits the use of different torque maps for different transmissions. The feature reduces the number of software part numbers that are required for operation. The feature protects the transmission from excessive torque.The selection of "Multi-Torque" and "Dual Horsepower" is available through Caterpillar