check engine MITSUBISHI MONTERO 1998 Workshop Manual

coolant is 176-203F (80-95C). Turn engine off. Insert a paper clip
in engine speed detection connector. See Fig. 3. Connect a tachometer
to paper clip.
Fig. 3: Locating Engine Speed Detection Connector (3000GT - DOHC)
Courtesy of Mitsubishi Motor Sales of America
3) Install a timing light. Start engine and allow it to idle.
Using tachometer, read curb idle (RPM). Multiply RPM reading by 3 to
obtain actual curb idle speed. Ensure curb idle speed is 600-700 RPM.
Turn engine off. Curb idle speed is automatically controlled by Idle
Air Control (IAC) system. If curb idle speed is not as specified, see
DTC P0505 in G - TESTS W/CODES article.
4) Disconnect waterproof female connector from Brown ignition
timing check connector. See Fig. 4. Using a jumper wire, ground
ignition timing check terminal to read basic ignition timing. Using
timing light, read basic ignition timing value. See
IGNITION TIMING SPECIFICATIONS table. If basic ignition timing is
within specification, go to next step. If basic ignition timing is not
within specification, see DTC P0335 in G - TESTS W/CODES article.
5) Remove jumper wire to read actual ignition timing. Using
timing light, read actual ignition timing value. If actual ignition
timing is not within specification, see DTC P0335 in G - TESTS W/CODES
article.

Fig. 4: Locating Ignition Timing Check Connector
Courtesy of Mitsubishi Motor Sales of America
3000GT (SOHC)
1) Ignition timing is controlled by Powertrain Control Module
(PCM) and is not adjustable. Manufacturer provides procedure for
checking timing.
2) Start engine and warm engine until engine temperature
coolant is 176-203
F (80-95C). Turn engine off. Insert a paper clip
in noise filter connector. See Fig. 5. Connect a tachometer to paper
clip.
Fig. 5: Locating Noise Filter Connector
Courtesy of Mitsubishi Motor Sales of America
3) Install a timing light. Start engine and allow it to idle.
Using tachometer, read curb idle speed (RPM). Ensure curb idle speed

is 600-700 RPM. Turn engine off. Curb idle speed is automatically
controlled by Idle Air Control (IAC) system. If curb idle speed is not\
as specified, see DTC P0505 in G - TESTS W/CODES article.
4) Disconnect waterproof female connector from Brown ignition
timing check connector. See Fig. 4. Using a jumper wire, ground
ignition timing check terminal to read basic ignition timing. Using
timing light, read basic ignition timing value. See
IGNITION TIMING SPECIFICATIONS table. If basic ignition timing is
within specification, go to next step. If basic ignition timing is not
within specification, see DTC P0335 in G - TESTS W/CODES article.
5) Remove jumper wire to read actual ignition timing. Using
timing light, read actual ignition timing value. If actual ignition
timing is not within specification, see DTC P0335 in G - TESTS W/CODES
article.
All Other Models
1) Ignition timing is controlled by Powertrain Control Module
(PCM) and is not adjustable. Manufacturer provides procedure for
checking timing. On models with distributor, DO NOT attempt to adjust
ignition timing by rotating distributor.
2) Connect scan tool to Data Link Connector (DLC). DLC is
located below dash, near steering column. See Fig. 2. Install a timing
light. Start engine and allow it to idle.
3) Using scan tool, read curb idle speed (RPM). Ensure curb
idle speed is about 750 RPM. Turn engine off. Curb idle speed is
automatically controlled by Idle Air Control (IAC) system. If curb
idle speed is not as specified, see DTC P0505 in G - TESTS W/CODES
article.
CAUTION: MFI system actuator test must be cancelled or test will
continue to run for 27 minutes. Driving vehicle under this
condition may damage engine.
4) Using scan tool, select MFI SYSTEM ACTUATOR TEST, then
select item 17 (BASIC IGNITION TIMING). Read basic ignition timing
value. See IGNITION TIMING SPECIFICATIONS table. If basic ignition
timing is within specification, go to next step. If basic ignition
timing is not within specification, cancel MFI system actuator test.
See DTCS P0100 (except Mirage 1.5L), P0105, P0115 and P0335 in G -
TESTS W/CODES article.
5) Read actual ignition timing value. If actual ignition
timing is not within specification, cancel MFI system actuator test.
See DTCS P0100 (except Mirage 1.5L), P0105, P0115 and P0335 in G -
TESTS W/CODES article.
IDLE SPEED & MIXTURE
* PLEASE READ THIS FIRST *
NOTE: Perform adjustments with engine at normal operating
temperature, cooling fan and accessories off, transmission
in Park or Neutral, and front wheels in straight-ahead
position.
BASIC IDLE SPEED
NOTE: Basic idle speed adjustment information on Eclipse 2.0L
non-turbo engine is not available from manufacturer at time
of publication.
3000GT
1) Ensure vehicle is at normal operating temperature with all

lights, cooling fan and accessories off. Shift transmission into
Neutral or Park position.
2) If not using scan tool, go to next step. Connect scan tool
to Data Link Connector (DLC). DLC is located below dash, near steering\
column. See Fig. 2. Go to step 5).
3) On DOHC models, insert a paper clip in engine speed
detection connector. See Fig. 3. On SOHC models, insert paper clip in
noise filter connector. See Fig. 5. On all models, connect a
tachometer to paper clip.
4) Connect a jumper wire between ground and Data Link
Connector (DLC) terminal No. 1. See Fig. 2. Disconnect waterproof
female connector from Brown ignition timing check connector. See
Fig. 4 . Using a jumper wire, ground ignition timing check terminal.
5) Start engine and allow it to idle. Check basic idle speed.
See IDLE SPEED SPECIFICATIONS table. On DOHC models, multiply
tachometer reading by 3 to obtain actual basic idle speed. If idle
speed is not within specification, turn engine speed adjusting screw
until correct engine speed is obtained. See Fig. 6. Access to speed
adjusting screw is obtained by removing rubber plug on throttle body.
6) If idle speed cannot be lowered by turning engine speed
adjusting screw, determine if Throttle Position (TP) sensor has been
moved. Adjust TP sensor if necessary. See TP SENSOR ADJUSTMENT under
THROTTLE POSITION (TP) SENSOR. If TP sensor is okay, replace throttle
body.
Fig. 6: Adjusting Idle Speed (Typical)
Courtesy of Mitsubishi Motor Sales of America
IDLE SPEED SPECIFICATIONS TABLE









\









\









\









\









\









\







Application Curb Idle Basic Idle
1.5L & 1.8L ............ 600-800 ............... 650-750
2.0L
Non-Turbo ............ 700-900 ................... (1)
Turbo ................ 650-850 ............... 700-800
2.4L ................... 650-850 ............... 700-800
3.0L & 3.5L ............ 600-800 ............... 650-750
( 1) - Information is not available from manufacturer at time
of publication.









\









\









\









\









\









\







NOTE: Basic idle speed should only be adjusted after verifying
spark plugs, fuel injectors, idle air control motor and
engine compression are okay.
All Other Models
1) Ensure vehicle is at normal operating temperature with all
lights, cooling fan and accessories off. Shift transmission into
Neutral or Park position.
2) Basic idle speed can only be adjusted using a scan tool to
ground Data Link Connector (DLC). Connect scan tool to DLC. DLC is
located below dash, near steering column. See Fig. 2.
3) Start engine and allow it to idle. Using scan tool, select
MFI SYSTEM ACTUATOR TEST, then select item 30. Check basic idle speed.
See IDLE SPEED SPECIFICATIONS table.
CAUTION: MFI system actuator test must be cancelled or test will
continue to run for 27 minutes. Driving vehicle under this
condition may damage engine.
4) Cancel MFI system actuator test. If idle speed is not
within specification, turn engine speed adjusting screw until correct
engine speed is obtained. See Fig. 6. Access to speed adjusting screw
is obtained by removing rubber plug on throttle body.
5) If idle speed cannot be lowered by turning engine speed
adjusting screw, determine if fixed Speed Adjusting Screw (SAS). Fixed\
SAS is stop screw contacting throttle lever. See
FIXED SPEED ADJUSTING SCREW for procedure.
6) After all adjustments are verified to be correct, possible
cause of incorrect idle speed is deterioration of Idle Air Control
(IAC) circuit. See DTC P0505 in G - TESTS W/CODES article.
CURB (SLOW) IDLE SPEED
NOTE: Curb idle speed is controlled by Idle Air Control (IAC)
motor. Adjustment is usually not necessary. For curb idle
speed specifications, see IDLE SPEED SPECIFICATIONS table
under BASIC IDLE SPEED.
1) Check ignition timing and adjust if necessary. See
IGNITION TIMING . Run engine at 2000-3000 RPM for more than 5 seconds.
Allow engine to idle for 2 minutes. Check curb idle speed.
2) If curb idle speed is not within specification, check IAC
system. See DTC P0505 in G - TESTS W/CODES article. If IAC system is
okay, adjust basic idle speed. See BASIC IDLE SPEED.
FIXED SPEED ADJUSTING SCREW
NOTE: Fixed Speed Adjusting Screw (SAS) is preset by manufacturer
and usually does not require adjustment. Only adjust fixed
SAS if other adjustment procedures require it, or if

MIXTURE. Perform all adjustments with engine at normal
operating temperature, front wheels in straight-ahead
position, cooling fan and all accessories off, and
transmission in Park or Neutral.
Eclipse 2.0L Non-Turbo
1) TP sensor is not adjustable. Disconnect TP sensor
connector. Using external ohmmeter, measure resistance between TP
sensor terminals No. 1 and 3. See Fig. 8. If resistance is not 3500-
6500 ohms, replace TP sensor.
2) While slowly rotating throttle valve from idle to full
open, measure resistance between TP sensor terminals No. 2 and 3. If
resistance does not change smoothly in proportion to throttle opening,
replace TP sensor.
Montero
1) Disconnect TP sensor connector. Using jumper wires,
connect an external ohmmeter between TP sensor terminals No. 1 and 2.
See Fig. 9 . Insert .025" (.65 mm) feeler gauge between fixed speed
adjusting screw and throttle lever.
2) Loosen TP sensor mounting screws and rotate TP sensor
fully clockwise. Ensure there is continuity between terminals No. 1
and 2. Rotate TP sensor counterclockwise until there is no continuity,
and tighten screws. Install Test Harness (MB991348) between TP sensor
and harness connector.
3) Turn ignition on. Using external voltmeter, measure TP
sensor output voltage between terminals No. 1 and 3. If voltage is not
.4-1.0 volt, check harness and sensor. See DTC P0120 in G - TESTS
W/CODES article.
All Other Models
1) Disconnect TP sensor connector. Using jumper wires,
connect an external ohmmeter between TP sensor terminals No. 1 and 2
on Diamante or No. 3 and 4 on all other models. See Fig. 9. On
Diamante and Mirage 1.8L with cruise control, insert .055" (1.40mm)
feeler gauge between fixed speed adjusting screw and throttle lever.
On Galant, insert .025" (.65 mm) feeler gauge between fixed speed
adjusting screw and throttle lever. On all other models, insert .018"
(.45 mm) feeler gauge between fixed speed adjusting screw and throttle\
lever.
2) Loosen TP sensor mounting screws and rotate TP sensor
fully counterclockwise. Ensure there is continuity between terminals
No. 1 and 2 on Diamante, or No. 3 and 4 on all other models. Rotate TP
sensor clockwise until there is no continuity and tighten screws.
Install Test Harness (MB991348) between TP sensor and harness
connector.
3) Turn ignition on. Using external voltmeter, measure TP
sensor output voltage between terminals No. 1 and 3 on Diamante, or
No. 2 and 4 on all other models. If voltage is not .4-1.0 volt, check
harness and sensor. See DTC P0120 in G - TESTS W/CODES article.
Fig. 8: TP Sensor Connector Terminals (Eclipse 2.0L Non-Turbo)
Courtesy of Mitsubishi Motor Sales of America

1) Start and run engine at 2000 RPM. Ensure battery is fully
charged. Turn defogger switch to ON position. Using a voltmeter, check
voltage at center section of each defogger grid filament.
2) If voltage is about 6 volts, grid filament is okay. If
voltage is about 12 volts, an open is present in negative circuit.
Move probe slowly toward negative terminal to determine location of
open circuit.
3) If voltage is zero volts, an open is present in positive
circuit. Move probe slowly toward positive terminal to determine
location of open circuit. Repair grid as necessary. See
GRID FILAMENT REPAIR under ON-VEHICLE SERVICE.
ON-VEHICLE SERVICE
GRID FILAMENT REPAIR
Clean broken wire tips thoroughly. Place masking tape along
both sides of broken wire. See Fig. 8. Apply Repair Paste (DuPont
4817) to broken section of grid. Remove masking tape after paste has
dried. Wait 24 hours before using defogger.
Fig. 8: Repairing Rear Defogger Grid Element
REMOVAL & INSTALLATION
DEFOGGER SWITCH
Removal & Installation (Diamante)
Defogger switch is integral with A/C system ECU. To remove
A/C ECU, remove center console. Remove audio panel. Remove radio.
Remove A/C ECU. To install, reverse removal procedure.
Removal & Installation (Eclipse)
Remove upper stoppers from glove compartment. Drop down glove
compartment. From glove compartment opening, reach behind center air
outlet assembly and disconnect harness connectors to switches. Release
metal clips from center air outlet assembly. Remove center air outlet.
Remove defogger switch from center air outlet. To install, reverse
removal procedure.
Removal & Installation (Galant)

NOTE: Whenever transmission or drivetrain service is performed
that affects the suspension alignment, for example,
removing the engine cradle, it is required that the
alignment be checked and corrected if necessary.
AUTOMATIC TRANSMISSION/TRANSAXLE ASSEMBLIES
AUTOMATIC TRANSMISSION/TRANSAXLE ASSEMBLY INSPECTION








\









\









\









\









\









\









\


Condition Code Procedure
Any internal component
failure that requires
removal of the assembly
from the vehicle for
service. ( 1) ........... A ........... ( 2) Require repair or
replacement of the automatic
transmission/transaxle
assembly.
( 1) - It is Required that the torque converter and all other
failure related components be inspected for cause and
condition.
( 2) - For components not requiring removal of the assembly,
refer to the component listing in this document.









\









\









\









\









\









\









\


DIFFERENTIAL AND FINAL DRIVE ASSEMBLIES
NOTE: Does not include half shafts.
DIFFERENTIAL AND FINAL DRIVE ASSEMBLY INSPECTION









\









\









\









\









\









\









\


Condition Code Procedure
Any internal component
failure that requires
removal of the assembly
from the vehicle for
service. ( 1) ........... A ... Require repair or replacement
of the differential assembly.
( 1) - For components not requiring removal of the assembly,
refer to the component listing in this document.









\









\









\









\









\









\









\


MANUAL TRANSMISSION/TRANSAXLE ASSEMBLIES
MANUAL TRANSMISSION/TRANSAXLE ASSEMBLY INSPECTION








\









\









\









\









\









\









\


Condition Code Procedure
Any internal component
failure that requires
removal of the assembly
from the vehicle for
service. ( 1) ........... A ... Require repair or replacement
of the manual
transmission/transaxle
assembly.
( 1) - For components not requiring removal of the assembly,

usage on specific models, see appropriate wiring diagram in
L - WIRING DIAGRAMS article. For theory and operation on each
output component, refer to system indicated after component.
Data Link Connector (DLC)
See SELF-DIAGNOSTIC SYSTEM .
EGR Control Solenoid Valve
See EXHAUST GAS RECIRCULATION (EGR) CONTROL under EMISSION
SYSTEMS.
Fuel Injectors
See FUEL CONTROL under FUEL SYSTEM.
Fuel Pressure Control Solenoid Valve (Turbo)
See FUEL DELIVERY under FUEL SYSTEM.
Fuel Pressure Regulator
See FUEL DELIVERY under FUEL SYSTEM.
Idle Air Control (IAC) Motor
See IDLE SPEED under FUEL SYSTEM.
Malfunction Indicator Light
See SELF-DIAGNOSTIC SYSTEM .
Power Transistor(s) & Ignition Coils
See IGNITION SYSTEMS .
Purge Control Solenoid Valve
See EVAPORATIVE CONTROL under EMISSION SYSTEMS.
Wastegate Control Solenoid Valve
See TURBOCHARGED ENGINES under AIR INDUCTION SYSTEM.
FUEL SYSTEM
FUEL DELIVERY
Electric fuel pump, located in gas tank, feeds fuel through
in-tank fuel filter, external fuel filter (located in engine
compartment) and fuel injector rail.
Fuel Pump
Fuel pump consists of a motor-driven impeller. Pump has an
internal check valve to maintain system pressure, and a relief valve
to protect fuel pressure circuit. Pump receives voltage supply from
MFI control relay.
Fuel Pressure Control Solenoid Valve (Turbo)
Valve prevents rough idle due to fuel percolation. On engine
restart, if engine coolant or intake air temperature reaches a preset
value, PCM applies voltage to fuel pressure control solenoid valve for
2 minutes after enginerestart. Valve will open, allowing atmospheric
pressure to be applied to fuel pressure regulator diaphragm. This
allows maximum available fuel pressure at injectors, enriching fuel
mixture and maintaining stable idle at high engine temperatures.
Fuel Pressure Regulator
Located on fuel injector rail, this diaphragm-operated relief
valve adjusts fuel pressure according to engine manifold vacuum.
As engine manifold vacuum increases (closed throttle), fuel

cylinder is on its exhaust stroke when plug fires.
HALL EFFECT IGNITION SYSTEM
This system is equipped with a Hall Effect distributor.
Shutter(s) attached to distributor shaft rotate through distributor
Hall Effect switch, also referred to as a Camshaft Position (CMP)
sensor, which contains a distributor pick-up (a Hall Effect device and
magnet). As shutter blade(s) pass through pick-up, magnetic field is
interrupted and voltage is toggled between high and low. PCM uses this
data along with Crankshaft Position (CKP) sensor data to control
ignition timing and injector pulse width to maintain optimum
driveability.
Power Transistor & Ignition Coil
Power transistor is mounted inside distributor with disc and
optical sensing unit. When ignition is on, ignition coil primary
circuit is energized. As distributor shaft rotates, disc rotates,
triggering optical sensing unit. PCM receives signals from optical
sensing unit. Signals are converted and sent to power transistor,
interrupting primary current flow and inducing secondary voltage.
IGNITION TIMING CONTROL SYSTEM
Ignition timing is controlled by PCM. PCM adjusts timing
based on various conditions such as engine temperature, altitude and
detonation.
EMISSION SYSTEMS
EXHAUST GAS RECIRCULATION (EGR) CONTROL
Federal Emissions (Non-Turbo)
To lower oxides of nitrogen (NOx) exhaust emissions, a non-
computer controlled exhaust gas recirculation system is used. EGR
operation is controlled by throttle body ported vacuum. Vacuum is
routed through vacuum control valve to prevent EGR operation at low
engine temperatures.
Spring pressure holds EGR valve closed during low vacuum
conditions (engine idling or wide open throttle). When vacuum pressure\
increases and overcomes EGR spring pressure, EGR valve is lifted to
allow exhaust gases to flow into intake manifold for combustion.
California Emissions & Turbo
PCM controls EGR operation by activating EGR control solenoid
valve according to engine load. When engine is cold, PCM signals EGR
control solenoid valve to deactivate EGR.
EGR Control Solenoid Valve
Valve denies or allows vacuum supply to EGR valve based on
PCM commands.
EVAPORATIVE CONTROL
Fuel evaporation system prevents fuel vapor from entering
atmosphere. System consists of special fuel tank with vapor separator
tanks (if equipped), vacuum relief filler cap, overfill limiter (2-wa\
y
valve), fuel check valve, thermovalve (if equipped), charcoal
canister, purge control valve, purge control solenoid valve, and
connecting lines and hoses.
Purge Control Solenoid Valve