: As the plunger reaches the bottom of its stroke, fuel from the supply tank floods the barrel through inlet ports .
: When you press the accelerator, a control rack rotates the plunger. This changes the position of the helix, determining how long the spill port stays covered and, consequently, how much fuel is delivered to the cylinder. Common Pump Types in Animations Fuel Injection pump working principle - Animation
: To stop injection, a helical groove on the plunger eventually uncovers a spill port . This allows pressurized fuel to "spill" back into the lower-pressure gallery, causing the delivery valve to close instantly. : As the plunger reaches the bottom of
If you'd like to explore a specific part of the system further, I can help you with: A deeper look at the and how it meters fuel. Comparing mechanical governors vs. electronic ECU control. Common Pump Types in Animations : To stop
The difference between and indirect injection nozzles.