ME-SFI vehicle features - AH07.61-P-0002-02A

ENGINE 112.910/911/912/913/914/916/917/920/921/922/923/940/941/942/943/944/946/947/949/953/954/955/970/972/973/975 

ENGINE 113.940/941/942/943/944/948/960/961/963/965/966/967/968/969/980 

Control unit ME 2.0 

Control unit ME 2.0 with 6 connector plugs (A - F), input and output signals matched.

Control unit ME 2.8 as of approx. 06/00 

Control unit ME 2.8 with 5 connector plugs (1 to 5). The aluminum ME-SFI control unit has a shell-type standard housing.

Input signals from the following sensors: 

• Coolant temperature sensor
• Intake air temperature sensor (integrated in hot film mass air flow sensor)
• Hot film mass air flow sensor
• Throttle valve actuator (actual value potentiometer)
• Oil sensor (oil level/oil temperature/oil quality)
• Variable cruise control push button/cruise control push button
• Circuit 50 from electronic ignition lock control unit (start detection)
• P/N information from EGS control unit
• Clutch pedal switch (manual transmission)
• Back-up lamp switch (manual transmission)
• Tank pressure sensor
• Intake manifold pressure sensor

for national version

with cylinder deactivation

and with ME 2.8 as of 06/00

• Crankshaft position sensor (increment)
• Camshaft Hall sensor
• O2 sensors
• Knock sensors
• Accelerator pedal sensor (set value potentiometer)

Output signals: 

• Ignition coil actuation (one double ignition coil per cylinder)
• Actuation of fuel injection valves
• Actuation of throttle valve actuator
• Actuation of fuel pump relay
• Output of PWM signal for exhaust gas recirculation/pressure transducer
• Actuation of air injection
• Actuation of intake manifold switchover
• Actuation of purging switchover valve
• Actuation of O2 sensor heater
• Output of engine speed signal "TNA"
• Actuation of activated charcoal canister shutoff valve
• Output of PWM signal for fan control (phased in, production startup with viscous fan)
• Actuation of starter relay
• Data line for fault memory.

Information relating to CAN data bus:

• Operating states of BAS/ESP or BAS/ASR
• Operating states of EGS
• Operating states of SBC
• Operating states of electronic accelerator
• Target engine torque reduction/increase of ASR/ESP
• Torque interface of EGS
• Gear recognition
• Transmission overload protection
• Wheel speeds (vehicle speed and acceleration)
• Brake light switch
• Instrument cluster (indicator lamps, warning tone, oil level, oil temperature, oil quality, "fuel system OPEN" warning , signal for fuel consumption, coolant temperature, intake air temperature, engine speed)
• Refrigerant compressor ON/OFF, refrigerant pressure.

Ignition system 

The engines are equipped with dual ignition. Owing to the valve arrangement, two spark plugs per cylinder are beneficial in order to optimize exhaust emission values and ensure smooth engine running. Each spark plug is actuated separately via its own ignition coil by the engine control unit. Both ignition coils of a cylinder are combined to form a dual ignition coil. In the lower partial load range up to approx. 2000 rpm, both ignition sparks of a cylinder are triggered simultaneously. At medium and high loads, ignition is offset by up to 10° CKA. The order of actuation is constantly varied in this case in order to ensure uniform wear of both spark plugs and to avoid deposits on one side of the combustion chamber.

Coolant temperature sensor 

Smaller design with appropriate connector. Inserted into a hole at front of engine middle and sealed with O-ring. Attached by means of spring clasp.

Oil sensor (oil level, oil temperature, oil quality) 

The oil level, oil temperature and oil quality are detected by means of an oil sensor installed in the oil pan. The sensor operates in accordance with the capacitive measuring principle and features integrated electronics which detects the three signals. The information is passed in the form of a PWM signal to the ME-SFI control unit and via the CAN to the instrument cluster. The oil quality is measured for the demand-based oil change interval display. The oil quality is detected on the basis of the capacitance of the engine oil (dielectric), this being as much as 6 times greater if the oil quality is poor. The measuring range for the oil level is 80 mm (normal level ±0 mm), accuracy approx. ±3 mm. The oil sensor is supplied with power from the ME-SFI control unit.

O2 sensors upstream of CAT 

Along each exhaust path, a O2 sensor is screwed into the front exhaust pipe close to the engine. Lambda control is performed separately for the right and left cylinder bank.

O2 sensors downstream of CAT and low emission EURO3/4 

The O2 sensors downstream of the CAT are arranged downstream of the firewall catalytic converter.

Intake manifold switchover 

With engine 112, 113, to improve torque the intake manifold is switched between a long and short intake tract via a pneumatically actuated flap at the front of the intake manifold. The resonance intake manifold switchover valve is actuated by the ME-SFI control unit.

Fuel supply 

The fuel return line and the diaphragm pressure regulator at the fuel distributor rail are no longer present (single-line system). The fuel pressure regulator is already integrated in the fuel filter. Excess fuel flows from the fuel filter and back into the fuel tank.

Either a fuel pump (helical spindle pump) is installed at the fuel pump assembly or a two-stage fuel pump is installed in the fuel feed module (model 163, 203, 209, 211).

Air injection and low emission EURO3/4 

The electric air pump is located at the front of the engine. A combination valve (air shutoff valve and check valve) is flange-mounted at the front of the cylinder head of each cylinder bank. The air pump switchover valve is operated parallel to the electric air pump.

Exhaust gas recirculation 

A combined exhaust gas recirculation valve with electrical pressure transducer is installed behind the right cylinder bank. The pressure transducer is actuated by the ME-SFI/HMS control unit by means of a PWM signal. It is actuated in line with the map as a function of engine speed, engine load, coolant temperature, idling speed and full throttle detection. The EGR valve is opened to a varying extent as a result of this actuation with a vacuum of approx. 80 to 220 mbar and the quantity of exhaust gases which are recirculated is controlled in this way. NOx formation is reduced further.

Speedtronic (without ) 

Additional cruise control functions are the variable vehicle speed limiter and the individually programmable permanent maximum speed. This requires the variable cruise control push button (S40/4) with slide switch. The shift signals from the variable cruise control push button are transmitted via the CAN data bus to the ME-SFI control unit.

Evaporative emission control system 

Larger activated charcoal canister. Purging system with leak test.

Fuel system 

During refueling the fuel vapors are collected at the filler neck and passed to the activated charcoal canister (ORVR = Onboard Refueling Vapor Recovery). The system is not planned for model 163.

Exhaust system and low emission EURO3/4 

Each exhaust path has a firewall catalytic converter.

ME 2.8 as of 06/00 

Engines 112 and 113 are equipped with the new gasoline injection and ignition system ME 2.8 (successor of ME 2.0). New features are:

• Housing of ME-SFI control unit and contacts modified
• Intake manifold pressure sensor (B28) for detecting altitude at start and for testing exhaust gas recirculation
• Modified electrical contacts on throttle valve actuator
• O2 sensors of type LSH 4.7 (Bosch). Sensor heater output is approx. 7 W when warm (previously 18 W).
• Exhaust concept EURO3/4

Flexible Fuel Vehicle (FFV) 

Engine 112.946 as of 15.7.02 with code 929 

FFV vehicles can be fueled with premium fuel or with ethanol (ethanol component 85%). This creates mixtures in the fuel tank with an ethanol concentration of 0 to 85%. The proportion of ethanol is taught in at every filling of the tank and the mixture formation is adjusted accordingly.