VEHICLE ELECTRICAL ELECTRONIC AND TELEMATIC SYSTEMS ANALYSIS AND DESIGN

p Engine Management : 2006 Mercedes-Benz C-Class (Fuel Injection , Spark Ignition and Emissions

Engine Management System ensure that engines run cleanly and efficiently in a wide variety of conditions , they are for the most part reliable and require little or no maintenance . Two basic functions performed by an EMS (1 ) to meter fuel to the engine in the right quantity and (2 ) to provide a spark at the right time

An EMS is a self contained custom built computer which controls the running of an engine by monitoring the engine speed , load and

br temperature and providing the ignition spark at the right time for the prevailing conditions and metering the fuel to the engine in the exact quantity required

There are two discrete subsystems in operation within the EMS

The fuel or injection system and

The ignition system

When the engine is running its requirements for fuel and ignition timing will vary according to certain engine conditions , the main two being engine speed and engine load . This Map injection gives the appropriate fuel or timing setting for each possible speed and load condition . There will normally be a map for the injector timings (fuel map ) and a separate map for the ignition timing settings (ignition map ) within the EMS . Each map has entries for a pre-determined range of engine speeds (called speed sites ) and a predetermined range of engine load conditions (called load sites , which generally indicate how far open the throttle is . The EMS knows the engine speed (derived from the crank sensor or distributor pickup ) and the engine load (from the Throttle Position Sensor or airflow meter ) and will use these two values to `look-up ' the appropriate fuel and timing settings in each map . If the current engine telemetry falls between the sites in the map then the value is interpolated between the nearest two sites . Normally there will be speed sites every 500 or so RPM and 8 to 16 load sites between closed and open throttle . In the example below speed sites are spaced every 1000-RPM and the eight load sites are numbered 0 to 7

An all-new line of V6 engines , with more horsepower , powers the 2006 Mercedes-Benz C-Class and more advanced technology than before . The luxury models feature a high-tech seven-speed automatic transmission and the C350 Luxury sedan has the classic Mercedes balance of ride quality and handling . The line also includes sport models for those who want a sportier driving experience . Inside , the C-Class cars look and feel like a Mercedes-Benz , with firm , supportive seats and mostly high-quality materials . The C-Class delivers Mercedes engineering and safety technology , with optional all-wheel-drive that will improve traction in wet or wintry conditions

New engines for 2006 complement the substantial C-Class updates made just a year ago . Mercedes redesigned the C-Class interior for 2005 freshened the exterior styling and further distinguished the sport models from the standard luxury sedans . A new six-speed manual transmission greatly improved shift action . New paint technology imbeds microscopic ceramic flakes in the clear coat...