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Fuel System, Basic Function - GF47.00-P-9900A

Engine All (4xWD) 

Engine All (CAR) 

G16142899Courtesy of MERCEDES-BENZ USA

Sample diagram of low-pressure and high-pressure fuel circuit 

Overview 

This document contains information on:

General 

The fuel system provides the combustion engine with fuel in all operating ranges by means of the fuel supply system and mixture formation system.

Function requirements 

Function 

The fuel system consists of the fuel supply system (low-pressure fuel circuit) and the mixture formation system (high-pressure fuel circuit).

The fuel supply system supplies the fuel from the fuel tank (5) to the highpressure fuel pump (9).

The mixture formation system consists of the high-pressure fuel circuit and the injection control. The function of the mixture formation is to compress the fuel via the high-pressure fuel pump (9), store the fuel pressure in the fuel distributor (2) and make this available to the fuel injectors (4) depending on the operating status. To form an optimal fuel/air mixture, the fuel injectors (4) inject the fuel directly into the combustion chamber in a needs-based manner.

Key components of fuel supply system (low-pressure fuel circuit):

Key components of mixture formation system (high-pressure fuel circuit):

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