SENR9977 19 Systems Operation Section 1. The ECU sends a signal to the timing solenoid valve. 2. The timing mechanism is triggered by the timing solenoid valve. 3. The timing solenoid valve changes the pressure in the timing mechanism. 4. The timing mechanism changes the position of the cam ring. 5. The cam ring changes the position of the rollers. 6. The rollers change the position of the cam plate. 7. The cam plate changes the timing of the fuel delivery.
Control g01133210 Illustration 19 Timing advance for timing mechanism (side view and top view) g01143278 Illustration 21 Electronic control for the fuel system (typical example) The ECU for the injection pump uses the command from the ECM and the measured values from the speed/timing sensor to actuate the fuel solenoid valve. g01133211 Illustration 20 Timing retard for timing mechanism (side view and top view) The timing advance or the timing retard of the fuel injection pump is shown in the following steps: