BMW S58, Руководство пользователя

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S58�Engine
8.�Intake�Air�and�Exhaust�System
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• Rapid�operating�readiness�<�7�s
• Higher�heater�output�at�10�W
• Increased�temperature�compatibility
• Improved�system�connector�with�better�contact�properties
The�LSU�5.2�has�an�extended�measuring�range.�It�is�thus�possible�to�measure�precisely�from�oxygen
sensor�0.65�and�higher.�The�new�oxygen�sensor�is�operational�earlier,�meaning�exact�measured�values
are�available�after�only�7�s.
The�measuring�dynamics�of�the�sensor�is�higher,�whereby�it�is�possible�to�determine�the�air/fuel�ratio
in�each�cylinder�separately�and�thus�also�control�it.�As�a�result,�a�homogeneous�exhaust�flow�can�be
adjusted,�the�emission�levels�lowered�and�the�long-term�emission�behavior�optimized.
8.2.6.�Monitoring�oxygen�sensor
The�oxygen�sensor�after�the�catalytic�converter�is�also�called�a�monitoring�sensor.�The�monitoring
sensor�LSF�XFOUR�from�Bosch�is�used�which�is�the�successor�sensor�to�the�LSF�4.2.
The�LSF�Xfour�needs�the�DME�8.6.S�for�signal�analysis�and�is�distinguished�by�the�following
characteristics:
• To�achieve�quicker�response�characteristics�after�engine�start�(half�of�the�LSF�4.2�value),
a�stronger�controlled�heater�has�been�integrated�in�the�LSF�Xfour.
• This�improves�signal�stability.
• Less�space�is�required�for�installation.
• Thanks�to�the�high�temperature�resistance�and�optimal�thermoshock�protection,�the
resistance�to�condensation�in�the�exhaust�tract�following�a�cold�start�has�been�improved.
Depending�on�the�conditioning�of�the�emission�control�systems,�it�may�take�around�30�seconds
for�the�full�power�of�the�engine�to�be�available�after�it�is�started.�In�that�period,�the�DME�control�unit
activates�a�substitute�program�that�is�required�in�order�to�quickly�bring�the�emission�control�systems
up�to�operating�temperature.�In�that�situation�the�full�power�of�the�engine�is�not�available�as�normal.�If
necessary,�the�driver�is�notified�of�the�situation�by�a�CCM�(check�control�message).
8.2.7.�Rear�silencer
The�rear�silencer�has�the�typical�M�chrome-plated�exhaust�tailpipe�trims.
The�electrical�exhaust�flaps�are�activated�directly�by�the�DME�by�a�pulse-width�modulated�signal.