BMW S58, Руководство пользователя

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S58�Engine
10.�Fuel�Preparation
78
Index Explanation
8 Fuel�pressure�sensor
9 Holding�clamp
10 Solenoid�valve�injector
11 Rail�pressure�sensor
10.2.�Low-pressure�fuel�system
The�F97/F98�with�S58�engine�is�fitted�with�a�65-liter�fuel�tank.
The�fuel�is�delivered�from�the�fuel�tank�through�the�electric�fuel�pump�via�the�feed�line�at�a�primary
pressure�of�5�bar�to�the�high�pressure�pumps.�The�fuel�is�conveyed�from�the�electric�fuel�pump�as
required.
To�monitor�the�fuel�pressure,�a�fuel�low-pressure�sensor�is�used�that�measures�and�monitors�the�fuel
pressure�on�the�low-pressure�side.�The�fuel�low-pressure�sensor�is�connected�to�and�monitored�by�the
DME.
In�the�event�of�a�failure�of�the�fuel�pressure�sensor�the�electric�fuel�pump�continues�to�operate�at�100%
delivery�rate�with�terminal�15�ON.
10.3.�High-pressure�fuel�system
For�the�S58�engine,�the�high-pressure�injection�HDE�6�is�used.
Changes�were�made�in�regard�to�the�fuel�injection�pressure,�which�can�now�range�up�to�350�bar.
Increasing�the�fuel�injection�pressure�from�200�bar�to�350�bar�results�in�the�following�advantages:
• Improved�fuel�atomization
• More�efficient�delivery
• Reduced�fuel�wall�film�formation
• Shorter�injection�periods
These�advantages�due�to�the�fuel�injection�pressure�increase�to�350�bar�led�to�the�following
improvements:
• Reduction�in�particle�emissions
• Improved�engine�response�under�high�engine�load
• Improved�engine�response�under�M�dynamic�engine�operation
Bosch�high-pressure�fuel�injection�valves�with�the�designation�HDEV�6�with�CVO�are�used.�Due�to
the�fuel�system�pressure�increase�from�200 bar�to�350 bar,�the�solenoid�valve�injectors�HEDV6�were
optimized�using�suitable�materials�and�coatings.