DME control unit

2.3 DME control unit

The DME control unit Continental SDI 9 is installed at the top right of the engine compartment; the wiring harness is routed directly to the engine without any connection points.

The high-performance electronic engine control unit EMS SDI 9 from Continental is used for the 911 Carrera (991) engines. This control unit has been specially designed to meet the requirements for use of direct fuel injection (DFI) and VarioCam Plus. Of particular significance here is control of the injectors, which are central elements of the direct fuel injection system. The engine control also controls the throttle position (electronic throttle) as this is a prerequisite for the Porsche Stability Management (PSM) system installed as standard.

The modern DME control unit allows sequential injection of fuel into the combustion chamber for each cylinder at precisely defined time intervals. This helps to minimize fuel consumption and reduce emissions, even during dynamic driving. Each cylinder receives precisely the amount of fuel that corresponds to the engine load condition in order to achieve an optimum air/fuel ratio.

Brief overview of DME features

New DME components

• 6 hole injectors • Differential Hall-effect sensor on the crankshaft • Pressure sensor on the intake manifold for load detection • Tank leakage diagnostic system (NVLD) for USA vehicles

New functions of the DME control unit

• Thermal management • Auto Start Stop function (Porsche Doppelkupplung [PDK] and manual transmission) • Coasting (vehicles with Porsche Doppelkupplung [PDK] only) • Variable deceleration fuel cutoff • Vehicle electrical system recuperation DME engine electronics 2

DME engine electronics 2

2_407_11 General overview of DME functions

• Thermal management • Auto Start Stop function • Variable deceleration fuel cutoff • Vehicle electrical system recuperation • Direct fuel injection (DFI) • Low-pressure fuel supply • Returnless fuel system • High-pressure fuel supply (quantity control valve) • Electronic throttle • Electronic throttle with idle speed control • VarioCam Plus (intake camshaft) • Demand-controlled variable oil pump • Switchable resonator on the air cleaner housing • Tuning flap on the intake system (Carrera S only) • Intake system sound symposer • Stereo lambda control circuits • Flap control on the intake system (Carrera S and sports exhaust system) • Static high-voltage ignition distribution (individual ignition coils with integrated drivers) • Cylinder-specific knock control (with 2 knock sensors) • 2 electric radiator fans (continuously variable) • 2 engine compartment purge fans (2-stage) • Differential Hall-effect sensor (detects engine speed, reference mark and direction of rotation of the engine • Pressure sensor on the intake manifold (detects intake manifold pressure and intake air temperature) • On-board diagnosis for monitoring the emission control system

CAN networking

In addition to the sensors and actuators that are connected directly to the DME control unit, the DME control unit also has access to other data, which is assigned to other control units as input or output variables. This external data is accessed via the internal high-speed network, the so-called CAN (Controller Area Network) bus.