fuel pressure MITSUBISHI LANCER EVOLUTION IV 1998 User Guide

MPI – Troubleshooting13-6
TROUBLESHOOTING
1. DIAGNOSIS FUNCTION
1-1 ENGINE WARNING LAMP (CHECK ENGINE LAMP)
If an abnormality occurs in any of the following items related
to the Multipoint Fuel Injection (MPI) system, the engine
warning lamp will illuminate.
If the lamp remains illuminated or if the lamp illuminates while
the engine is running, check the diagnosis code output.
Engine warning lamp inspection items
Engine-ECU
Air flow sensor (AFS)
Intake air temperature sensor
Throttle position sensor (TPS)
Engine coolant temperature sensor
Crank angle sensor
Camshaft position sensor
Barometric pressure sensor
Detonation sensor
Injector
Ignition coil, power transister
Misfire
1-2 METHOD OF READING AND ERASING DIAGNOSIS
CODES
(1) Use the special tool to earth No.1 terminal (diagnosis
control terminal) of the diagnosis connector.
(2) To check ABS system, remove the valve relay.
NOTE
That is because the valve relay is off and the warning
lamp remains illuminated if there is a fault in the ABS
system.
(3) Turn off the ignition switch.
(4) Read out a diagnosis code by observing how the warning
lamp flashes.
Indication of diagnosis code by warning lamp
When the diagnosis code No.24 is outputWhen no diagnosis code is output*
On
Off
1.5 secs.0.5 sec.
0.5 sec.
Pause
time 3
secs.Tens signalPlace
division
2 secs.Units signal
A03X0113
On
Off
0.5 sec.
0.25 sec.
NOTE
*: Even if the ABS system is normal, removing the valve relay causes the diagnosis code No.52 to
be output.
Engine warning lamp
(check engine lamp)

MPI – Troubleshooting13-7
1-3 ERASING DIAGNOSIS CODES
(1) Turn the ignition switch to OFF.
(2) After disconnecting the battery cable from the battery (–) terminal for 10 seconds or more, reconnect
the cable.
(3) After the engine has warmed up, run it at idle for about 15 minutes.
1-4 FAIL-SAFE FUNCTION REFERENCE TABLE
When the main sensor malfunctions are detected by the diagnosis function, the vehicle is controlled
by means of the pre-set control logic to maintain safe conditions for driving.
Malfunctioning itemControl contents during malfunction
Air flow sensor (AFS)(1) Uses the throttle position sensor signal and engine speed signal (crank angle sensor
signal) to take reading of the basic injector drive time and basic ignition timing from
the pre-set mapping.
(2) Fixes the ISC servo in the appointed position so idle control is not performed.
Intake air temperature
sensorControls as if the intake air temperature is 25C.
Throttle position
sensor (TPS)No increase in fuel injection amount during acceleration due to the throttle position sensor
signal.
Engine coolant
temperature sensorControls as if the engine coolant temperature is 80C.
(This condition is maintained until the ignition switch is turned off even when the sensor signal
returns normal.)
Camshaft position
sensor(1) Injects fuel to all cylinders simultaneously for 4 seconds.
(However, after the ignition switch is turned to ON, the No. 1 cylinder top dead centre
is not detected at all.)
(2) Lets the fan motor (radiator and condensor) run at high speed.
Barometric pressure
sensorControls as if the barometric pressure is 101 kPa {760 mmHg}.
Detonation sensorSwitches the ignition timing from ignition timing for super petrol to ignition timing for standard
petrol.
Ignition coil, power
transistorCuts off the fuel supply to cylinders with an abnormal ignition.
Alternator FR terminalDoes not control the output of the alternator according to an electrical load. (works as a
normal alternator)
Misfire
(Evolution-V only)Cuts off the fuel to the misfiring cylinder if a misfire that could damage the catalyst is detected.

MPI – Troubleshooting13-22
6. ENGINE-ECU INSPECTION
6-1 TERMINAL VOLTAGES
Engine ECU connector
Terminal
No.Check itemCheck condition (Engine condition)Normal condition
1No.1 injectorWhile engine is idling after having been warmed up,
suddenly depress the accelerator pedal
Momentarily drops
slightlyfrom 1114V
14No.2 injector
suddenly depress the accelerator pedal.slightly from 11 – 14 V.
2No.3 injector
15No.4 injector
3Fuel pressure control
valve
Ignition switch: ONBattery voltage
valve
Engine: Cranking to idling (within about two minutes)0 – 3 V to battery
voltage
4Stepper motor coil (A1)Engine: Immediately after engine has been started
f
or warming up
Changes repeatedly
f
rom battery voltage to
17Stepper motor coil (A2)
for warming upfrom battery voltage to
0 – 6 V and from 0 – 6
V to battery voltage5Stepper motor coil (B1)V to battery voltage.
18Stepper motor coil (B2)
6Secondary air control
solenoid valveIgnition switch: ONBattery voltage
8Fuel pump relayIgnition switch: ONBattery voltage
Engine: Idling0 – 3 V
10Power transistor unit
(A)Engine speed: 3,000 r/min0.3 – 3.0 V
23Power transistor unit
(B)
11Wastegate solenoid
valve
Ignition switch: ONBattery voltage
valve
Engine: At idle after having been warmed up (when
premium gasoline is used)0 – 3 V
12Power supplyIgnition switch: ONBattery voltage
25
19Air flow sensor reset
signal
Engine: Idling0 – 1 V
signal
Engine speed: 3,000 r/min6 – 9 V
20Fan motor relay (HI)Fan not operating (coolant temperature: 90C or
below)Battery voltage
Fan at high speed (coolant temperature: 105C or
above)0 – 3 V

MPI – Troubleshooting13-23
Terminal
No.Normal condition Check condition (Engine condition) Check item
21Fan motor relay (LOW)Fan not operating (coolant temperature: 90C or
below)Battery voltage
Fan at low speed (coolant temperature: 90 – 100C)0 – 3 V
22A/C relayEngine: Idling
A/C switch: OFF to ON (Compressor is being
driven.)Battery voltage, or 6 V
or more instanta-
neously to 0 – 3 V
33Alternator G terminalEngine: Warm, idle (radiator fan: OFF)
Headlamp: OFF to ON
Brake lamp: OFF to ON
Rear defogger switch: OFF to ONVoltage rises by 0.2 –
3.5 V.
36Engine warning lampIgnition switch: OFF → ON0 – 3 V → Battery
voltage (After several
seconds have
elapsed)
37Power steering fluid
pressure switchEngine: Idling after
warming upWhen steering wheel is
stationaryBattery voltage
When steering wheel is
turned0 – 3 V
38Control relayIgnition switch: OFFBattery voltage
Ignition switch: ON0 – 3 V
39Fuel pump relay No.2While engine is idling, suddenly depress the
accelerator pedal.Momentarily rises
slightly from 0 to 3 V.
40Exhaust temperature
warning lampIgnition switch: OFF to ON0 – 3 V to battery
voltage (After several
seconds have
elapsed)
41Alternator FR terminalEngine: Warm, idle (radiator fan: OFF)
Headlamp: OFF to ON
Brake lamp: OFF to ON
Rear defogger switch: OFF to ONVoltage drops by 0.2 –
3.5 V.
45A/C switchEngine: Idle speedTurn the A/C switch OFF0 – 3 V
Turn the A/C switch ON
(A/C compressor is oper-
ating)Battery voltage
60Oxygen sensor heater
(Evolution V only)
Engine: Idling0 – 3 V
(Evolution-V only)
Engine speed: 5,000 r/minBattery voltage
71Ignition switch-STEngine: Cranking8 V or more

MPI – Troubleshooting13-25
6-2 RESISTANCE AND CONTINUITY BETWEEN HARNESS SIDE CONNECTORS AND
TERMINALS
Engine-ECU Harness Side Connector Terminal Arrangement
Terminal No.Inspection itemNormal condition (Check condition)
1 – 12No.1 injector2 – 3 Ω (At 20C)
14 – 12No.2 injector
2 – 12No.3 injector
15 – 12No.4 injector
3 – 12Fuel pressure control valve28 – 36 Ω (At 20C)
4 – 12Stepper motor coil (A1)28 – 33 Ω (At 20C)
17 – 12Stepper motor coil (A2)
5 – 12Stepper motor coil (B1)
18 – 12Stepper motor coil (B2)
6 – 12Secondary air control solenoid valve28 – 36 Ω (At 20C)
11 – 12Wastegate solenoid valve62 – 74 Ω (At 20C)
13 – Body earthEngine-ECU earthContinuity established (0 Ω)
26 – Body earth
60 – 12Oxygen sensor heater (EVOLUTION-V
only)11 – 18 Ω (at 20C)
72 – 92Intake air temperature sensor5.3 – 6.7 kΩ (When intake air temperature is 0C)
2.3 – 3.0 kΩ (When intake air temperature is 20C)
1.0 – 1.5 kΩ (When intake air temperature is 40C)
0.30 – 0.42 kΩ (When intake air temperature is 80C)
74 – 77High temperature sensor3 Ω or less
83 – 92Engine coolant temperature sensor5.1 – 6.5 kΩ (When coolant temperature is 0C)
2.1 – 2.7 kΩ (When coolant temperature is 20C)
0.9 – 1.3 kΩ (When coolant temperature is 40C)
0.26 – 0.36 kΩ (When coolant temperature is 80C)
87 – 92Idle position switchContinuity established (when throttle valve is at idle
position)
No continuity (when throttle valve is slightly open)
91 – Body earth–Continuity established

MPI – On-vehicle Service13-30
ON-VEHICLE SERVICE
1. IDLE POSITION SWITCH AND THROTTLE
POSITION SENSOR (TPS) ADJUSTMENT
The thickness of the feeler gauge inserted between the fixed
SAS and throttle lever should be 0.45 mm.
2. FIXED SAS ADJUSTMENT

Turn down one turn after the fixed SAS has touched the
throttle lever.

Turn down 1-1/4 turns after the fixed SAS has touched the
throttle lever.
3. BASIC IDLE SPEED ADJUSTMENT
The basic idle speed should be 850 ± 50 rpm.
4. FUEL PRESSURE MEASUREMENT
The fuel pressure gauge should be installed at the location
shown on the left.

MPI – On-vehicle Service13-31
5. MPI SYSTEM COMPONENTS LAYOUT
NameSymbolNameSymbol
A/C switchQExhaust temperature warning lampS
A/C relayHFuel pressure control valveA
Air flow sensor (with a built-in intake air temperaturesensor and barometric pressure sensor)FIgnition coil and power transistor unitLsensor and barometric pressure sensor)InjectorB
Camshaft position sensorMISC servoD
Control relay and fuel pump relayPOxygen sensorK
Coolant temperature sensorEPower steering fluid pressure switchI
Crank angle sensorJSecondary air control solenoid valveN
Detonation sensorCThrottle position sensor (with a built-in idle switch)D
Diagnosis connectorR
Engine ECUOVehicle speed sensorT
Engine warning lampSWastegate solenoid valveG

MPI – On-vehicle Service13-34
9. INJECTOR CHECK
Injection Condition Check
(1) Release the residual pressure from the fuel pipe line to
prevent fuel from flowing out.
(2) Remove the injector.
(3) Set up the special tools (Injector Test Set, Adapter, Fuel
Pressure Regulator, and Clip) as illustrated below.
(4) From here on, use the same procedure as with the
conventional 4G9 engine for the check.
MD998741
MD998706 MB991607Main hose
BatteryInjectorClip: MD998746Return hose
Fuel Pressure Regulator: MD116395
10. RESISTOR CHECK
(1) Disconnect the resistor connector.
(2) Measure resistance across terminals as detailed below.
Standard value
Measurement terminalsResistance (Ω)
1 – 3
4 – 3
5 5 to 6 5 (at 20C)
5 – 3
5.5 to 6.5 (at 20C)
6 – 3
Resistor

MPI – Injector13-36
INJECTOR
REMOVAL AND INSTALLATION
Pre-removal Operation
(1) Fuel Discharge Prevention
(2) Air Hose D Removal
(Refer to GROUP15 – Intercooler.)Post-installation Operation
(1) Air Hose D Installation
(Refer to GROUP15 – Intercooler.)
(2) Fuel Leakage Check
O-ring
9 {0.9}83, 6
11
12
O-ring 10 – 13 {1.0 – 1.3}
Engine oil
1
2 3
4
5
6 78 9
10 11 12
Unit: Nm {kgf
m}
4
Removal steps
1. Injector connector
2. PCV hose connection
A3. High-pressure fuel hose connection
4. Fuel return hose connection
5. Vacuum hose connector
A6. Fuel pressure regulator7. Fuel return pipe
A8. Delivery pipe
9. Insulator
10. Insulator
AA11. Injector
12. Grommet

INTAKE AND EXHAUST – Intake Manifold15-9
INTAKE MANIFOLD
REMOVAL AND INSTALLATION
Pre-removal Operation
(1) Fuel Discharge Prevention
(2) Throttle Body Removal (Refer to GROUP 13.)
(3) Front Exhaust Pipe Removal (Refer to P.15-14.)
(4) Air Control Valve Bracket Removal (Refer to P.15-8.)
(5) Strut Tower Bar RemovalPost-installation Operation
(1) Strut Tower Bar Installation
(2) Air Control Valve Bracket Installation
(Refer to P.15-8.)
(3) Front Exhaust Pipe Installation (Refer to P.15-14.)
(4) Throttle Body Installation (Refer to GROUP 13.)
O-ring
Unit: Nm {kgf
m}
15
Engine oil
3 {0.3} 10 – 13 {1.0 – 1.3}
10 – 12
{1.0 – 1.2}
12 – 15 {1.2 – 1.5}
35 {3.6}
9 {0.9}30 {3.1}35 {3.6}20 {2.0}22 {2.2}20 {2.0}
14 14
167
5
17
1521
3
4 6
7 7
19
20
18 8
9 12
1011
13
Removal steps
1. Center cover
2. Ignition coil connector connection
3. Oxygen sensor connector connec-
tion
4. Crank angle sensor connector con-
nection
5. Injector connector connection
6. PCV hose
7. Vacuum hose connection
8. Brake booster vacuum hose con-
nection
9. Vacuum tank, solenoid valve, and
vacuum hose assembly10. Intake manifold stay
11. Oil level gauge guide assembly
12. Vacuum hose and pipe mounting
bolt
13. Fuel return hose connection
A14. Fuel high pressure hose connection
A15. Delivery pipe, injector, and pres-
sure regulator assembly
16. Insulator
17. Insulator
18. Alternator brace stay
19. Intake manifold
20. Intake manifold gasket