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How the Common Rail Pressure Accumulator Works

Model: (Various brands) Various
Part: Checks and maintenance

This video explains how the pressure accumulator (commonly referred to as the "rail") of the Common Rail works: its function is to accumulate diesel at very high pressure, sent by the high-pressure pump, and distribute it uniformly and instantaneously to all injectors. The pressure can easily exceed 1,600 bar, and the rail acts as a "hydraulic flywheel" dampening the pulsations generated by the pump. From here, rigid pipes connect the rail to each injector, supplying fuel at the same pressure to all injectors, coming from a common volume (hence the name "Common Rail") and allowing for fine atomisation of the diesel and precise control of the quantity and timing of injection. It is equipped with a pressure sensor, a pressure relief valve, and a pressure regulator.

Posted on 24 April 2026 by ScegliAuto

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How to Open a Stuck Boot on the Peugeot 407?

On the Peugeot 407, the boot may become stuck, possibly due to a problem with the control button or the lock actuator. In such cases, you can perform an emergency opening by following the simple procedure shown in this tutorial. First, open the rear doors, then lower the seat back by operating the release lever. Next, go inside the boot, locate the lock, and manually operate it using a flathead screwdriver. The boot will then be free to open.

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