check engine MITSUBISHI MONTERO 1998 Workshop Manual
[x] Cancel search | Manufacturer: MITSUBISHI, Model Year: 1998, Model line: MONTERO, Model: MITSUBISHI MONTERO 1998Pages: 1501, PDF Size: 25.81 MB
Page 461 of 1501

When engine is off, fuel vapors are vented into charcoal
canister. When engine is warmed to normal operating temperature and
running at speeds greater than idle, PCM energizes purge control
solenoid valve, allowing vacuum to purge valve.
Canister vapors are then drawn through solenoid valve into
intake manifold for burning. Purge control solenoid valve remains
closed during idle and engine warm-up to reduce HC (hydrocarbons) and
CO (carbon monoxide) emissions.
POSITIVE CRANKCASE VENTILATION (PCV) VALVE
PCV valve operates in closed crankcase ventilation system.
Closed crankcase ventilation system consists of PCV valve, oil
separator, breather and ventilation hoses.
PCV valve is a one-way check valve located in valve cover.
When engine is running, manifold vacuum pulls PCV valve open, allowing
crankcase fumes to enter intake manifold. If engine backfires through
intake manifold, PCV valve closes to prevent crankcase combustion.
SELF-DIAGNOSTIC SYSTEM
NOTE: PCM diagnostic memory is retained by direct power supply
from battery. Memory is not erased by turning off ignition,
but it will be erased if battery or PCM is disconnected.
Self-diagnostic system monitors input and output signals
through the Data Link Connector (DLC). Diagnostic Trouble Codes (DTCs\
)
can only be read using a scan tester. For additional information, see
G - TESTS W/CODES article.
Malfunction Indicator Light (MIL)
MIL (CHECK ENGINE light) comes on when ignition is turned on.\
MIL remains on for several seconds after engine has started. If an
abnormal input signal occurs, MIL comes on and code is stored in
memory. If an abnormal input signal returns to normal, PCM turns MIL
off, but code remains stored in memory until it is cleared. If
ignition is turned on again, MIL will not come on until PCM detects
malfunction during system operation.
Page 477 of 1501

Fuel Pump Check Connector Taped to wiring harness, on
right side of firewall.
Ignition Timing Adjustment
Connector Taped to wiring harness, on
right side of firewall.
Ignition Coil Top left side of engine.
Page 496 of 1501

Wire lead conductors
exposed ................ B .. Require repair or replacement.
Wire lead corroded ...... A .. Require repair or replacement.
Wire lead open .......... A .. Require repair or replacement.
Wire lead shorted ....... A .. Require repair or replacement.
(1) - Refer to manufacturer's diagnostic trouble code procedure
and require repair or replacement of affected
component(s).
( 2) - Determine cause and correct prior to repair or replacement
of part.
( 3) - Determine source of contamination, such as engine
coolant, fuel, metal particles, or water. Require
repair or replacement.
( 4) - Inoperative includes intermittent operation or out of OEM
specification. Some components may be serviceable; check
for accepted cleaning procedure.
\
\
\
\
\
\
\
CRUISE CONTROL BRAKE SWITCHES
See SWITCHES.
CRUISE CONTROL CABLES
See CRUISE CONTROL LINKAGES AND CABLES .
CRUISE CONTROL CLUTCH SWITCHES
See SWITCHES.
CRUISE CONTROL LINKAGES AND CABLES
CRUISE CONTROL LINKAGE AND CABLE INSPECTION \
\
\
\
\
\
\
Condition Code Procedure
Attaching hardware
broken ................. A ... Require repair or replacement
of hardware.
Attaching hardware
missing ................ C .......... Require replacement of
hardware.
Attaching hardware not
functioning ............ A ... Require repair or replacement
of hardware.
Bent .................... A .. Require repair or replacement.
Binding ................. A .. Require repair or replacement.
Bracket bent, affecting
performance ............ A .. Require repair or replacement.
Bracket bent, not
affecting performance .. .. ........ No service suggested or
required.
Bracket broken, affecting
performance ............ A ............ Require replacement.
Bracket broken, not
affecting performance .. .. ........ No service suggested or
required.
Bracket corroded,
affecting performance .. A .. Require repair or replacement.
Bracket corroded, not
affecting performance .. 2 .. Suggest repair or replacement.
Page 533 of 1501

EMISSION CONTROL VISUAL INSPECTION PROCEDURES
1998 Mitsubishi Montero
1983-98 GENERAL INFORMATION
Emission Control Visual Inspection Procedures
All Models
* PLEASE READ THIS FIRST *
This article is provided for general information only. Not
all information applies to all makes and models. For more complete
information, see appropriate article(s) in the ENGINE PERFORMANCE
Section.
EMISSION CONTROL LABELS
The vehicle manufacturer's emission control label, also known
as the underhood tune-up label or Vehicle's Underhood Emission Control
System (VECI) label, is located in the engine compartment. Information\
regarding year model of vehicle, engine size, number of cylinders,
emission equipment or type, engine tune-up specifications, whether
vehicle was manufactured for sale in California or is a Federal
vehicle, vacuum hose routing schematic, etc., can be found on this
label. See Fig. 1.
In addition to the VECI label, some emission control
inspection and maintenance programs may require an additional label to
be affixed to the vehicle in special circumstances. For example, in
California, a Bureau Of Automotive Repair (BAR) engine label may be
affixed to the left door post. A BAR engine label is only used when
the vehicle has an engine change, approved modification or is a
Specially Constructed (SPCN) or an acceptable Gray market vehicle.
Check your state's emission control inspection and maintenance laws to
determine if a similar label is used.
Fig. 1: Typical Emission Control Label
Courtesy of General Motors Corp.
EMISSION CONTROL VISUAL INSPECTION
* PLEASE READ THIS FIRST *
NOTE: The following emission control visual inspection procedures
should be used as a guide only. When performing a visual
inspection, always follow your state's recommended
Page 534 of 1501

inspection procedures.
A visual inspection is made to determine if any required
emission control devices are missing, modified or disconnected.
Missing, modified or disconnected systems must be made fully
operational before a vehicle can be certified.
POSITIVE CRANKCASE VENTILATION (PCV)
PCV controls the flow of crankcase fumes into the intake
manifold while preventing gases and flames from traveling in the
opposite direction. PCV is either an open or closed system. See Fig. 2
.
Ensure PCV system is installed as required. Verify valve,
required hoses, connections, flame arresters, etc., are present,
routed properly and in serviceable condition.
Fig. 2: Typical Open & Closed Type PCV System
THERMOSTATIC AIR CLEANER (TAC)
The TAC supplies warm air to air intake during cold engine
operation. This system is active during cold engine warm-up only.
Under all other operating conditions, air cleaner function is the same
as any non-thermostatic unit.
Ensure required exhaust shroud, hot air duct, vacuum hoses
and air cleaner components are present and installed properly. See
Fig. 3 . Ensure any required thermostatic vacuum switches are in place
and vacuum hoses are installed and in serviceable condition. Also
ensure air cleaner lid is installed right side up. Check for oversized
air filter elements and for additional holes in the air cleaner
housing.
Page 535 of 1501

Fig. 3: Typical Thermostatic Air Cleaner System
FUEL EVAPORATIVE SYSTEM (EVAP)
The EVAP system allows for proper fuel system ventilation
while preventing fuel vapors from reaching the atmosphere. This means
that vapors must be caught and stored while the engine is off, which
is when most fuel evaporation occurs. When the engine is started,
these fuel vapors can be removed from storage and burned. In most
systems, storage is provided by an activated charcoal (or carbon)
canister. See Fig. 4. On a few early systems, charcoal canisters are
not used. Instead, fuel vapors are vented into the PCV system and
stored inside the crankcase.
The main components of a fuel evaporation system are a sealed
fuel tank, a liquid-vapor separator and vent lines to a vapor-storing
canister filled with activated charcoal. The filler cap is normally
not vented to the atmosphere, but is fitted with a valve to allow both
pressure and vacuum relief.
Although a few variations do exist between manufacturers,
basic operation is the same for all systems. Check for presence of
vapor storage canister or crankcase storage connections when required.
Ensure required hoses, solenoids, etc., are present and connected
properly. Check for proper type fuel tank cap. Check for any non-OEM
or auxiliary fuel tanks for compliance and the required number of
evaporation canisters.
Page 544 of 1501

Spark control systems are designed to ensure the air/fuel
mixture is ignited at the best possible moment to provide optimum
efficiency and power and cleaner emissions.
Ensure vacuum hoses to the distributor, carburetor, spark
delay valves, thermal vacuum switches, etc., are in place and routed
properly. On Computerized Engine Controls (CEC), check for presence of\
required sensors (O2, MAP, CTS, TPS, etc.). Ensure they have not been
tampered with or modified.
Check for visible modification or replacement of the feedback
carburetor, fuel injection unit or injector(s) with a non-feedback
carburetor or fuel injection system. Check for modified emission-
related components unacceptable for use on pollution-controlled
vehicles.
AIR INJECTION SYSTEM (AIS)
Air Pump Injection System (AP)
The air pump is a belt-driven vane type pump, mounted to
engine in combination with other accessories. The air pump itself
consists of the pump housing, an inner air cavity, a rotor and a vane
assembly. As the vanes turn in the housing, filtered air is drawn in
through the intake port and pushed out through the exhaust port. See
Fig. 13 .
Check for missing or disconnected belt, check valve(s),
diverter valve(s), air distribution manifolds, etc. Check air
injection system for proper hose routing.
Fig. 13: Typical Air Pump Injection System
Courtesy of General Motors Corp.
Pulsed Secondary Air Injection (PAIR) System
PAIR eliminates the need for an air pump and most of the
associated hardware. Most systems consists of air delivery pipe(s),
pulse valve(s) and check valve(s). The check valve prevents exhaust
gases from entering the air injection system. See Fig. 14.
Ensure required check valve(s), diverter valve(s), air
distribution manifolds, etc., are present. Check air injection system
for proper hose routing.
Page 546 of 1501

EARLY FUEL EVAPORATION (EFE)
The EFE valve is actuated by either a vacuum actuator or a
bimetal spring (heat-riser type). The EFE valve is closed when engine
is cold. The closed valve restricts exhaust gas flow from the exhaust
manifold. This forces part of the exhaust gas to flow up through a
passage below the carburetor. As the exhaust gas quickly warms the
intake mixture, distribution is improved. This results in better cold
engine driveability, shorter choke periods and lower emissions.
Ensure EFE valve in exhaust manifold is not frozen or rusted
in a fixed position. On vacuum-actuated EFE system, check EFE thermal
vacuum valve and check valve(s). Also check for proper vacuum hose
routing. See Fig. 15.
Fig. 15: Typical Vacuum-Actuated EFE System
Courtesy of General Motors Corp.
EMISSION MAINTENANCE REMINDER LIGHT (EMR) (IF EQUIPPED)
Page 547 of 1501

If equipped, the EMR light (some models may use a reminder
flag) reminds vehicle operator that an emission system maintenance is
required. This indicator is activated after a predetermined
time/mileage.
When performing a smog check inspection, ensure EMR indicator
is not activated. On models using an EMR light, light should glow when
ignition switch is turned to ON position and should turn off when
engine is running.
If an EMR flag is present or an EMR light stays on with
engine running, fail vehicle and service or replace applicable
emission-related components. To reset an EMR indicator, refer to
appropriate MAINTENANCE REMINDER LIGHTS in the MAINTENANCE section.
MALFUNCTION INDICATOR LIGHT (MIL)
The Malfunction Indicator Light (MIL) is used to alert
vehicle operator that the computerized engine control system has
detected a malfunction (when it stays on all the time with engine
running). On some models, the MIL may also be used to display trouble
codes.
As a bulb and system check, malfunction indicator light will
glow when ignition switch is turned to ON position and engine is not
running. When engine is started, light should go out.
Page 548 of 1501

ENGINE OVERHAUL PROCEDURES - GENERAL INFORMATION
1998 Mitsubishi Montero
Engine Overhaul Procedures - General Information
ALL PISTON ENGINES
* PLEASE READ THIS FIRST *
Examples used in this article are general in nature and do
not necessarily relate to a specific engine or system. Illustrations
and procedures have been chosen to guide mechanic through engine
overhaul process. Descriptions of processes of cleaning, inspection,
assembly and machine shop practice are included.
Always refer to appropriate engine overhaul article in the
ENGINES section for complete overhaul procedures and specifications
for the vehicle being repaired.
ENGINE IDENTIFICATION
The engine may be identified from its Vehicle Identification
Number (VIN) stamped on a metal tab. Metal tab may be located in
different locations depending on manufacturer. Engine identification
number or serial number is located on cylinder block. Location varies
with manufacturer.
INSPECTION PROCEDURES
* PLEASE READ THIS FIRST *
NOTE: Always refer to appropriate engine overhaul article in the
ENGINES section for complete overhaul procedures and
specifications for the vehicle being repaired.
GENERAL
Engine components must be inspected to meet manufacturer's
specifications and tolerances during overhaul. Proper dimensions and
tolerances must be met to obtain proper performance and maximum engine
life.
Micrometers, depth gauges and dial indicator are used for
checking tolerances during engine overhaul. Magnaflux, Magnaglo, dye-
check, ultrasonic and x-ray inspection procedures are used for parts
inspection.
MAGNETIC PARTICLE INSPECTION
Magnaflux & Magnaglo
Magnaflux is an inspection technique used to locate material
flaws and stress cracks. The part in question is subjected to a strong
magnetic field. The entire part, or a localized area, can be
magnetized. The part is coated with either a wet or dry material that
contains fine magnetic particles.
Cracks which are outlined by the particles cause an
interruption in the magnetic field. The dry powder method of Magnaflux
can be used in normal light. A crack will appear as an obvious bright
line.
Fluorescent liquid is used in conjunction with a blacklight
in a second Magnaflux system called Magnaglo. This type of inspection
demands a darkened room. The crack will appear as a glowing line in
this process. Both systems require complete demagnetizing upon