Summary of the content on the page No. 1
Lotus Service Notes Section EMN
ENGINE MANAGEMENT & FUEL INJECTION
SECTION EMN - M111 ELISE
Section Page
Introduction & Component Location EMN.1 3
'Lotus Check' Scanner Tool EMN.2 4
Throttle Cable Adjustment EMN.3 7
Electronic Control Module (ECM) EMN.4 7
Relay Module EMN.5 8
Manifold Absolute Pressure (MAP) Sensor EMN.6 9
Crankshaft Position Sensor EMN.7 10
Engine Coolant Temperature (ECT) Sensor EMN.8 11
Intake Air Temperature (
Summary of the content on the page No. 2
Lotus Service Notes Section EMN COMPONENT LOCATION DIAGRAM em196 Page 2
Summary of the content on the page No. 3
Lotus Service Notes Section EMN EMN.1 - INTRODUCTION Key to Component Location Diagram 1. Fuel pump 14. Cam angle sensor (VVC only) 2. Engine coolant temperature (ECT) sensor 15. Idle air control (IAC) valve 3. Water temperature gauge sender (vertical) 16. Throttle postion (TP) sensor 4. Crankshaft position sensor 17. Throttle body 5. Oxygen sensor 18. Relay module 6. Intake air temperature (IAT) sensor 19. Data link connector (DLC) 7. Oil tempe
Summary of the content on the page No. 4
Lotus Service Notes Section EMN paired with 4, and 2 with 3), the spark in the cylinder on the exhaust stroke being 'wasted'. The twin coil pack is mounted on the cylinder block as for standard engines. On VVC engines, the variable valve control mechanism is also controlled by the ECM. Two solenoid valves attached to the hydraulic control unit on the inlet camshaft mechanism are used to distribute oil pres- sure either side of a piston in orde
Summary of the content on the page No. 5
Lotus Service Notes Section EMN Adaptor harness plugged into DLC MEMS 1.9 & switched to Power or MEMS 2J 'MEMS' harness programme card Printer Connect to battery Scanner tool em192 To Connect 'Lotus Check' To connect the equipment, proceed as follows: i). Plug the power harness into the scanner tool and the printer; ii). Insert the MEMS 1.9 (standard engine) or MEMS 2J (VVC engine) programme card into the scanner tool slot, label uppermos
Summary of the content on the page No. 6
Lotus Service Notes Section EMN test. Run a further test to verify the repair. Prog The 'programme' menu is available only on the MEMS 2J card, and allows matching of the engine management and security 5AS modules if one or the other is replaced. At the instant of ignition is switch on, the security 5AS module sends a unique coded signal to the engine management ECM, which must be recog- nised by the ECM before it will allow the engine to run.
Summary of the content on the page No. 7
Lotus Service Notes Section EMN EMN.3 - THROTTLE CABLE ADJUSTMENT Before adjusting the cable, first check that the pedal end of the cable is correctly located, and that the cable is correctly routed with no sharp bends or entrapment. Do not attempt to adjust the throttle cable or idle speed by means of the stop screw on the throttle body, which should not be disturbed. The throttle cable and associated components must be adjusted in a specific
Summary of the content on the page No. 8
Lotus Service Notes Section EMN Before removing an ECM, first disconnect the battery earth lead before pressing the retaining barb and unplugging the harness connector(s). On standard cars, the MAP sensor is contained within the ECM body, with the sensor hose connecting to a spigot on the underside of the unit. On pre 'boot box' cars, release the three screws securing the ECM to the side panel, and withdraw the unit. On post Sept. '98 'bootbo
Summary of the content on the page No. 9
Lotus Service Notes Section EMN Relay em197 module em222a MN.6 - MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR The MAP signal is fundamental to the calculation of air consumption and fuel calibration. The ECM provides a 5 volt supply and earth path to the sensor, which returns a voltage representing the manifold pressure. On standard engines, the MAP sensor is contained within the ECM and receives a signal from the intake plenum a
Summary of the content on the page No. 10
Lotus Service Notes Section EMN EMN.7 - CRANKSHAFT POSITION SENSOR The signals provided by the crankshaft position sensor enable the ECM to determine: - engine speed; - crankshaft position. The inductive type sensor is mounted by a single fixing into a flange at the right hand rear of the cylinder block, where it protrudes towards reluctor ring machined into the front face of the flywheel. Single fixing screw Crankshaft position sensor em20
Summary of the content on the page No. 11
Lotus Service Notes Section EMN EMN.8 - ENGINE COOLANT TEMPERATURE (ECT) SENSOR The ECM requires a coolant temperature input signal in order to increase fuel delivery and maintain driveability during the cold running and warm-up phase. The signal from this sensor is used for many different parameters within the engine management system to control and switch various components dependent on engine temperature. The sensor is a thermistor (a resisto
Summary of the content on the page No. 12
Lotus Service Notes Section EMN EMN.9 - INTAKE AIR TEMPERATURE (IAT) SENSOR The intake air temperature (IAT) sensor is fitted into the inlet manifold tract of no.4 cylinder, and is a transducer with a negative temperature coefficient, such that its electrical resistance reduces with increasing temperature. Using this signal in conjunction with that from the MAP sensor, the ECM is able to determine the air consumption of the engine, and adjust t
Summary of the content on the page No. 13
Lotus Service Notes Section EMN EMN.10 - THROTTLE POSITION (TP) SENSOR The throttle position (TP) sensor is a potentiometer fitted directly to the end of the throttle spindle, and provides the ECM with information on both throttle opening, and rate of change of throttle opening. For example, when a fully closed throttle and appropriate engine speed is signalled, the ECM activates the idle air control valve to regulate idle speed; a rapid or sud
Summary of the content on the page No. 14
Lotus Service Notes Section EMN EMN.11 - IDLE AIR CONTROL (IAC) VALVE The idle air control (IAC) valve is mounted on the intake plenum, and controls an air passage which by- passes the throttle valve. When the pintle of the valve is fully extended, the passage is closed off for a minimum idle speed, but as the ECM commands the IAC stepper motor to withdraw the pintle, a progressively greater amount of air is allowed to by-pass the throttle. In
Summary of the content on the page No. 15
Lotus Service Notes Section EMN EMN.12 - OXYGEN (O2) SENSOR The MEMS system operates a 'closed loop' fuel control system whereby the output signal from an oxygen sensor in the exhaust system is monitored by the ECM, which constantly adjusts the air/fuel ratio to that providing the most efficient conversion of gases by the catalyst. A lean air/fuel ratio causes a high exhaust oxygen content, which reduces the sensor output voltage to the ECM. T
Summary of the content on the page No. 16
Lotus Service Notes Section EMN EMN.13 - CAMSHAFT POSITION SENSOR (VVC versions only) The camshaft position sensor has two functions: i) to provide an engine position reference for the sequen- tial injection; ii) to measure the actual inlet cam period as controlled by the VVC mechanism. The inductive type sensor is mounted on the right hand side of the cylinder head and projects into the cam housing to be in close proximity to a toothed relucto
Summary of the content on the page No. 17
Lotus Service Notes Section EMN EMN.14 - VVC MECHANISM CONTROL SOLENOIDS The inlet cam period is determined by a hydraulic control unit (HCU) mounted on the right hand front of the cylinder head. The HCU uses two solenoids to operate a spool valve and control a piston and rack mechanism, which outputs from the HCU via a control shaft to the two VVC mechanisms. The ECM energises one solenoid valve at a time to drive the VVC mechanism either tow
Summary of the content on the page No. 18
Lotus Service Notes Section EMN EMN.15 - OIL TEMPERATURE SENSOR An oil temperature sensor is mounted in the top of the VVC hydraulic control unit. The oil temperature is used by the ECM to determine how quickly the VVC mechanism will respond to cam period change com- mands. To replace the sensor, unplug the electrical connector (brown), and unscrew from the hydraulic control unit. Fit a new seal onto the sensor before inserting and tightening
Summary of the content on the page No. 19
Lotus Service Notes Section EMN EMN.16 - FUEL SYSTEM The fuel system is a high pressure recirculating type, using an 'in tank' submerged 3-stage impeller pump, an in line canister filter, a common fuel rail supplying all four injectors, and a fuel pressure regulating valve controlling the return line to the tank. WARNING: The fuel line between pump and injector rail, and the injector rail itself, contain pressurised fuel both when the engine is
Summary of the content on the page No. 20
Lotus Service Notes Section EMN Fuel filler neck Filler breather hose Fuel filter Fuel pressure regulator valve Fuel tank Fuel pump Fuel rail Fuel injector Fuel feed line Fuel return line em208 Fuel Pump Switching The fuel pump is controlled by the ECM via the fuel pump relay located in the relay module, and is energised under the following conditions: . When the ignition is first switched on, the ECM grounds the pump relay coil for a few se
