MULTIPOINT FUEL INJECTION (MPI) <4G9> - 4x4 Brasil

1 MULTIPOINT FUELINJECTION (MPI)<4G9>13C-1 MULTIPOINT FUELINJECTION (MPI)<4G9>CONTENTSGENERAL2.. Outline of Changes2.. GENERAL INFORMATION2.. SERVICE SPECIFICATIONS5.. SEALANT5.. SPECIAL TOOLS6.. TROUBLESHOOTING8.. ON-VEHICLE SERVICE96.. Throttle Body (Throttle Valve Area) Cleaning96.. Throttle Position Sensor Adjustment96.. Basic Idle Speed Adjustment97.. fuel Pressure Test98.. fuel Pump Connector Disconnection (How to Reduce the fuel Pressure)100.. fuel Pump Operation Check100.. Component Location101.. Control Relay and fuel Pump Relay ContinuityCheck102.. Intake Air Temperature Sensor Check102.. engine Coolant Temperature SensorCheck102.. Throttle Position Sensor Check103.. Oxygen Sensor Check103.. Injector Check106.. Idle Speed Control (ISC) Servo (Stepper Motor)Check107.. Purge Control Solenoid Valve Check 108.. EGR Control Solenoid Valve Check108.. INJECTOR109.

2 THROTTLE BODY111.. MPI <4G9> General Information13C-2 GENERALOUTLINE OF CHANGESThe following contents have been established to correspond to the addition of vehicles with INFORMATIONThe MULTIPOINT fuel INJECTION System consistsof sensors which detect the engine conditions,the engine -ECU which controls the systembased on signals from these sensors, andactuators which operate under the control ofthe engine -ECU. The engine -ECU carries outactivities such as fuel INJECTION control, idlespeed control and ignition timing control. Inaddition, the engine -ECU is equipped withseveral diagnosis modes which simplifytroubleshooting when a problem INJECTION CONTROLThe injector drive times and injector timing arecontrolled so that the optimum air/ fuel mixtureis supplied to the engine to correspond to thecontinually-changing engine operation single injector is mounted at the intake portof each cylinder.

3 fuel is sent under pressurefrom the fuel tank by the fuel pump, with thepressure being regulated by the fuel pressureregulator. The fuel thus regulated is distributedto each of the INJECTION is normally carried out once foreach cylinder for every two rotations of thecrankshaft. The firing order is 1-3-4-2. This iscalled sequential fuel INJECTION . The engine -ECUprovides a richer air/ fuel mixture by carryingout open-loop control when the engine is coldor operating under high load conditions in orderto maintain engine performance. In addition,when the engine is warm or operating undernormal conditions, the engine -ECU controls theair/ fuel mixture by using the oxygen sensorsignal to carry out closed-loop control in orderto obtain the theoretical air/ fuel mixture ratiothat provides the maximum cleaningperformance from the three way AIR CONTROLThe idle speed is kept at the optimum speedby controlling the amount of air that bypassesthe throttle valve in accordance with changesin idling conditions and engine load during engine -ECU drives the idle speed control(ISC) motor to keep the engine running at thepre-set idle target speed in accordance withthe engine coolant temperature and airconditioner load.

4 In addition, when the airconditioner switch is turned off and on whilethe engine is idling, the ISC motor operatesto adjust the throttle valve bypass air amountin accordance with the engine load conditionsin order to avoid fluctuations in the engine TIMING CONTROLThe power transistor located in the ignitionprimary circuit turns ON and OFF to controlthe primary current flow to the ignition coil. Thiscontrols the ignition timing in order to providethe optimum ignition timing with respect to theengine operating conditions. The ignition timingis determined by the engine -ECU from theengine speed, intake air volume, engine coolanttemperature and atmospheric FUNCTIONDWhen an abnormality is detected in oneof the sensors or actuators related toemission control, the engine warning lamp(check engine lamp) illuminates as awarning to the an abnormality is detected in oneof the sensors or actuators, a diagnosiscode corresponding to the abnormality RAM data inside the engine -ECU thatis related to the sensors and actuators canbe read by means of the MUT-II.

5 In addition,the actuators can be force-driven undercertain <4G9> General Information13C-3 OTHER CONTROL FUNCTIONS1. fuel Pump ControlTurns the fuel pump relay ON so that currentis supplied to the fuel pump while the engineis cranking or A/C Relay ControlTurns the compressor clutch of the A/C ONand Fan Motor ControlThe revolutions of the radiator fan andcondenser fan are controlled in responseto the engine coolant temperature andvehicle Purge Control Solenoid Valve Control Refer to GROUP EGR Control Solenoid Valve ControlRefer to GROUP SPECIFICATIONSI temsSpecificationsThrottle bodyThrottle bore mm50 Throttle position sensorVariable resistor typeIdle speed control servoStepper motor type(Stepper motor type by-pass air control system) engine -ECUI dentification model flow sensorKarman vortex typeBarometric pressure sensorSemiconductor typeIntake air temperature sensorThermistor typeEngine coolant temperature sensorThermistor typeOxygen sensorZirconia typeVehicle speed sensorMagnetic resistive element typeInhibitor switchContact switch typeCamshaft position sensorMagnetic resistive element typeCrank angle sensorHall element typeDetonation sensorPiezoelectric typePower steering fluid pressure switchContact switch typeActuatorsControl relay typeContact switch typeFuel pump relayContact switch typeInjector type and numberElectromagnetic type.

6 4 Injector identification markCDH 210 EGR control solenoid valveDuty cycle type solenoid valvePurge control solenoid valveDuty cycle type solenoid valveFuel pressureregulatorRegulator pressure kPa329 MPI <4G9> General Information13C-4 CONTROL SYSTEM DIAGRAML1 Oxygen sensor <front>L2 Air flow sensorL3 Intake air temperaturesensorL4 Throttle position sensorL5 Camshaft position sensorL6 Crank angle sensorL7 engine coolant temperature sensorL8 Barometric pressuresensorL9 Detonation sensorL10 Oxygen sensor <rear>DPower supplyDIgnition switch-IGDI gnition switch-STDV ehicle speed sensorDA/C switchDA/C thermo sensorDInhibitor switchDPower steering fluidpressure switchDAlternator FR termi-nalDA/T-ECUE ngine-ECUl1 Injectorl2 Idle speed controlservol3 EGR control solenoidvalvel4 Purge control solenoid valveDEngine control relayDFuel pump relayDA/C relayDIgnition coilDFan motor relayDEngine warning lampDTachometerDDiagnosis outputDAlternator G terminalDA/T-ECUF romfuelpumpL5 Camshaft positionsensorL4 Throttle positionsensorL3 Intake air temperaturesensorL2 Air flow sensorL8 Barometric pressuresensorl4 Purge control solenoid valveL7 engine coolant temperature sensorL9 Detonation sensorL1 Oxygen sensor<front>L6 Crank angle sensorCanisterl3 EGR controlsolenoid valveTo fueltankl2 Idle speed control servoAir cleanerAirEGR valveCatalytic converterFuel pressureregulatorPCV valvel1 InjectorL10 Oxygen sensor<rear>EMAMPI <4G9> Service Specifications/Sealant13C-5 SERVICE SPECIFICATIONSI temsSpecificationsBasic idle speed r/min700 50 Throttle position sensor adjusting voltage mV535 735 Throttle position sensor resistance k

7 Speed control servo coil resistance 27 33 (at 20_C)Intake air temperature sensorresistance k 20_C13 17resistance k coolant temperaturesensor resistance k 20_C14 17sensor resistance k sensor output voltage (at racing) pressure kPaVacuum hose disconnection324 343 at curb idleVacuum hose connectionApprox. 265 at curb idleInjector coil resistance 13 16 (at 20_C)SEALANTItemSpecified sealantRemarkEngine coolant temperature sensor threaded portion3M Nut Locking Part No. 4171 or equivalentDrying sealantMPI <4G9> Special Tools13C-6 SPECIAL TOOLSToolNumberNameUseBACDMB991223A: MB991219B: MB991220C: MB991221D: MB991222 Harness setA: Test harnessB: LED harnessC: LED harness adapterD: ProbeDCheck at the ECU terminalsA: Connector pin contact pressure inspectionB: Power circuit inspectionC: Power circuit inspectionD.

8 Commercial tester connectionMB991502 MUT-II sub assemblyDReading diagnosis codeDMPI system inspectionMB991348 Test harness setDMeasurement of voltage during trouble-shootingDInspection using an analyzerMB991709 Test harnessDMeasurement of voltage during trouble-shootingDInspection using an analyzerDAdjustment of throttle position sensorMB991519 Alternator harnessconnectorMeasurement of voltage during troubleshoot-ingMD998478 Test harness (3-pin, triangle)DMeasurement of voltage during trouble-shootingDInspection using an analyzerMPI <4G9> Special Tools13C-7 ToolUseNameNumberMD998709 Adaptor hoseMeasurement of fuel pressureMD998742 Hose adaptorMB991637 fuel pressuregauge setMD998706 Injector test setChecking the spray condition of injectorsMB991607 Injector test harnessMD998741 Injector test adaptorMB991608 ClipMPI <4G9> Troubleshooting13C-8 TROUBLESHOOTINGDIAGNOSIS TROUBLESHOOTING FLOWR efer to GROUP 00 How to Use Troubleshooting/InspectionService the engine -ECU for vehicles for GCC is replaced, theimmobilizer-ECU and ignition key should be replaced togetherwith FUNCTIONENGINE WARNING LAMP (CHECK engine LAMP)If an abnormality occurs in any of the following items relatedto the MPI system, the engine warning lamp will illuminateor flash.

9 If the lamp remains illuminated or if the lamp illuminateswhile the engine is running, check the diagnosis code , the warning lamp will illuminate as bulb check forfive seconds whenever the ignition switch is turned to theON warning lamp inspection itemsCode item engine -ECUP0100 Air flow sensor systemP0105 Barometric pressure sensor systemP0110 Intake air temperature sensor systemP0115 engine coolant temperature sensor systemP0120 Throttle position sensor systemP0125 Feedback systemP0130 Oxygen sensor (front) system <sensor 1>P0135 Oxygen sensor heater (front) system <sensor 1>P0136 Oxygen sensor (rear) system <sensor 2>P0141 Oxygen sensor heater (rear) system <sensor 2>P0170 Abnormal fuel systemP0201No. 1 injector systemP0202No. 2 injector systemP0203No. 3 injector systemP0204No. 4 injector systemP0300 LIgnition coil (power transistor) systemP0301No.

10 1 cylinder misfire detectedP0302No. 2 cylinder misfire detectedP0303No. 3 cylinder misfire detectedP0304No. 4 cylinder misfire detectedP0325 Detonation sensor systemEngine warning lamp (check engine lamp)MPI <4G9> Troubleshooting13C-9 Code itemP0335 Crank angle sensor systemP0340 Camshaft position sensor systemP0403 EGR valve systemP0420 Catalyst malfunctionP0443 Purge control solenoid valve systemP0500 Vehicle speed sensor systemP0505 Idle speed control systemP0551 Power steering fluid pressure switch systemP1603 Battery backup line systemNOTE1. If the engine warning lamp illuminates because of a malfunction of the engine -ECU, communicationbetween MUT-II and the engine -ECU is impossible. In this case, the diagnosis code cannot be After the engine -ECU has detected a malfunction, the engine warning lamp illuminates when the engineis next turned on and the same malfunction is re-detected.