E - THEORY/OPERATION
1998 Mitsubishi Montero
1998 ENGINE PERFORMANCE
Mitsubishi - Theory & Operation
Diamante, Eclipse, Galant, Mirage, Montero, Montero Sport,
3000GT
INTRODUCTION
This article covers basic description and operation of engine
performance-related systems and components. Read this article before
diagnosing vehicles or systems with which you are not completely
familiar.
AIR INDUCTION SYSTEM
NON-TURBOCHARGED ENGINES
Mirage equipped with 1.5L engine uses a Manifold Absolute
Pressure (MAP) sensor instead of a Volume Airflow (VAF) sensor.
Filtered air is ducted to a plenum-mounted throttle body.
All other models use same basic air induction system using a
remote air filter (with VAF sensor) connected to a plenum-mounted
throttle body.
TURBOCHARGED ENGINES
In addition to basic air induction system, turbocharging
system components include turbocharger(s), charge air cooler(s), air\
by-pass valve(s), wastegate actuator(s), wastegate control solenoid
valve(s) and intake duct(s).
Wastegate Control Solenoid Valve(s)
Powertrain Control Module (PCM) energizes solenoid valve(s)\
,
controlling bleed-off rate of turbocharger pressure by wastegate
actuator(s).
COMPUTERIZED ENGINE CONTROLS
Sequential Fuel Injection (SFI) is a computerized engine
control system, which controls fuel injection, ignition timing, idle
speed and emission control systems.
POWERTRAIN CONTROL MODULE (PCM)
PCM, also known as Engine Control Module (ECM), receives and
processes signals from input devices. Operating conditions such as
cold starting, altitude, acceleration and deceleration affect input
device signals. Based on signals received, PCM sends signals to
various components, which control fuel injection, ignition timing,
idle speed and emission control systems. For PCM location, see
PCM LOCATION table.
PCM LOCATION TABLE
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Application Location
Eclipse 2.0L Non-Turbo .......... In Front of Left Front Strut Tower
manufacturer-recommended, maintenance. We encourage participating
service and repair shops (including franchisees and dealers) to adopt
(1) a Pledge of Assurance to their Customers and (2) the Motorist
Assurance Program Standards of Service. All participating service
providers have agreed to subscribe to this Pledge and to adhere to the
promulgated Standards of Service demonstrating to their customers that
they are serious about customer satisfaction.
These Standards of Service require that an inspection of the
vehicle's (problem) system be made and the results communicated to the\
customer according to industry standards. Given that the industry did
not have such standards, the Motorist Assurance Program successfully
promulgated industry inspection communication standards in 1994-95 for
the following systems: Exhaust, Brakes, ABS, Steering and Suspension,
Engine Maintenance and Performance, HVAC, and Electrical Systems.
Further, revisions to all of these inspection communication standards
are continually re-published.
In addition to these, standards for Drive Train and
Transmissions have recently been promulgated. Participating shops
utilize these Uniform Inspection & Communication Standards as part of
the inspection process and for communicating their findings to their
customers.
The Motorist Assurance Program continues to work
cooperatively and proactively with government agencies and consumer
groups toward solutions that both benefit the customer and are
mutually acceptable to both regulators and industry. We maintain the
belief that industry must retain control over how we conduct our
business, and we must be viewed as part of the solution and not part
of the problem. Meetings with state and other government officials
(and their representatives), concerned with auto repair and/or
consumer protection, are conducted. Feedback from these sessions is
brought back to the association, and the program adjusted as needed.
To assure auto repair customers recourse if they were not
satisfied with a repair transaction, the Motorist Assurance Program
offers mediation and arbitration through MAP/BBB-CARE and other non-
profit organizations. MAP conducted pilot programs in twelve states
before announcing the program nationally in October, 1998. During the
pilots, participating repair shops demonstrated their adherence to the
Pledge and Standards and agreed to follow the UICS in communicating
the results of their inspection to their customers. To put some
"teeth" in the program, an accreditation requirement for shops was
initiated. The requirements are stringent, and a self-policing method
has been incorporated which includes the "mystery shopping" of
outlets.
We welcome you to join us as we continue our outreach... with
your support, both the automotive repair industry and your customers
will reap the benefits. Please visit MAP at our Internet site www.
motorist.org or contact us at:
1444 I Street, NW Suite 700
Washington, DC 20005
Phone (202) 712-9042 Fax (202) 216-9646
January 1999
MAP UNIFORM INSPECTION GENERAL GUIDELINES
OVERVIEW OF SERVICE REQUIREMENTS & SUGGESTIONS
It is MAP policy that all exhaust, brake, steering,
suspension, wheel alignment, drive-line, engine performance and
maintenance, and heating, ventilation and air conditioning, and
electrical services be offered and performed under the standards and
procedures specified in these sections.
over connecting rod bolts. Install piston and connecting rod assembly.
Ensure piston notch, arrow or "FRONT" mark is toward front of engine.
See Fig. 17 .
Fig. 17: Installing Piston & Connecting Rod Assembly - Typical
This Graphic For General Information Only
Carefully tap piston into cylinder until rod bearing is
seated on crankshaft journal. Remove protectors. Install rod cap and
bearing. Lightly tighten connecting rod bolts. Repeat procedure for
remaining cylinders. Check bearing clearance. See
MAIN & CONNECTING ROD BEARING CLEARANCE in this article.
Once clearance is checked, lubricate journals and bearings.
Install bearing caps. Ensure marks are aligned on connecting rod and
cap. Tighten rod nuts or bolts to specification. Ensure rod moves
freely on crankshaft. Check connecting rod side clearance. See
CONNECTING ROD SIDE CLEARANCE in this article.
CONNECTING ROD SIDE CLEARANCE
Position connecting rod toward one side of crankshaft as far
as possible. Using feeler gauge, measure clearance between side of
connecting rod and crankshaft. See Fig. 18. Clearance must be within
specifications.
NOTE: Always refer to appropriate engine overhaul article in the
ENGINES section for complete overhaul procedures and
specifications for the vehicle being repaired.
CLEANING & INSPECTION
Clean camshaft with solvent. Ensure all oil passages are
clear. Inspect cam lobes and bearing journals for pitting, flaking or
scoring. Using micrometer, measure bearing journal O.D.
Support camshaft at each end with "V" blocks. Position dial
indicator with tip resting on center bearing journal. Rotate camshaft
and note reading. If reading exceeds specification, replace camshaft.
Check cam lobe lift by measuring base circle of camshaft
using micrometer. Measure again at 90 degrees to tip of cam lobe. Cam
lift can be determined by subtracting base circle diameter from tip of
cam lobe measurement.
Different lift dimensions are given for intake and exhaust
cam lobes. Reading must be within specifications. Replace camshaft if
cam lobes or bearing journals are not within specifications.
Inspect camshaft gear for chipped, eroded or damaged teeth.
Replace gear if damaged. On camshafts using thrust plate, measure
distance between thrust plate and camshaft shoulder. Replace thrust
plate if not within specification.
CAMSHAFT BEARINGS
Removal & Installation
Remove the camshaft rear plug. The camshaft bearing remover
is assembled with its shoulder resting on the bearing to be removed
according to manufacturer's instructions. Tighten puller nut until
bearing is removed. Remove remaining bearings, leaving front and rear
bearings until last. These bearings act as guide for camshaft bearing
remover.
To install new bearings, puller is rearranged to pull
bearings toward the center of block. Ensure all lubrication passages
of bearing are aligned with cylinder block. Coat new camshaft rear
plug with sealant. Install camshaft rear plug. Ensure plug is even
in cylinder block.
CAMSHAFT INSTALLATION
Lubricate bearing surfaces and cam lobes with ample amount of
Molykote or camshaft lubricant. Carefully install camshaft. Use care
not to damage bearing journals during installation. Install thrust
plate retaining bolts (if equipped). Tighten bolts to specification.
On overhead camshafts, install bearing caps in original location.
Tighten bolts to specification. Check end play.
CAMSHAFT END PLAY
Using dial indicator, check end play. Position dial indicator
on front of engine block. Position indicator tip against camshaft.
Push camshaft toward rear of engine and adjust indicator to zero.
Move camshaft forward and note reading. Camshaft end play
must be within specification. End play may be adjusted by relocating
gear, shimming thrust plate or replacing thrust plate depending on
manufacturer.
TIMING CHAINS & BELTS
FUEL TANKS
GAS CAPS
GASKETS
GROMMETS (VALVE COVER)
HARMONIC DAMPERS
HEATER CONTROL VALVES
HEATER CORES
HOSE AND TUBE COUPLERS, CONNECTORS AND CLAMPS
HOSE CLAMPS
HOSE CONNECTORS
HOSE COUPLERS
HOSES AND TUBES (FUEL LINES, RADIATOR, VACUUM, BY PASS,
HEATER, RECOVERY TANK AND OIL COOLERS)
HOUSINGS
IDLE AIR CONTROLS
IDLE SPEED CONTROL ACTUATORS
IGNITION BOOTS
IGNITION COIL TOWERS
IGNITION COILS
IGNITION CONTROL MODULES (ICM)
IGNITION SWITCHES
IGNITION TERMINALS
IGNITION WIRES, BOOTS, COIL TOWERS AND TERMINALS (SECONDARY)
IN-TANK FUEL STRAINERS
INERTIA FUEL SHUT-OFF SWITCHES
INTAKE AIR TEMPERATURE SENSORS
INTAKE MANIFOLDS
INTERCOOLERS
KNOCK SENSORS
LIQUID VAPOR SEPARATORS
MANIFOLD ABSOLUTE PRESSURE (MAP) SENSORS
MASS AIR FLOW (MAF) SENSORS
METAL AIR MANIFOLDS AND PIPES
METAL AIR PIPES
MIX CONTROL SOLENOIDS
MOTOR MOUNTS
O-RINGS, GASKETS, SEALS AND SPRING LOCKS
O2 SENSORS
OIL PRESSURE SENDING UNITS
OIL PUMP PICK-UP SCREENS
OIL PUMPS
PARK NEUTRAL POSITION SWITCHES
PCV BREATHER ELEMENTS
PCV ORIFICES
PCV VALVES
PICK-UP ASSEMBLIES (INCLUDES MAGNETIC, HALL EFFECT AND
OPTICAL)
POWER STEERING PRESSURE SENSORS
POWERTRAIN CONTROL MODULES (PCM) AND PROM
POWERTRAIN CONTROL PROM
PRESSURIZED EXPANSION TANK CAPS
RADIATOR CAPS AND PRESSURIZED EXPANSION TANK CAPS
RADIATOR FAN BLADES
RADIATOR FAN CLUTCHES
RADIATORS
ROLL OVER VALVES
SEALING COMPOUNDS
SEALS
SECONDARY AIR INJECTION SYSTEM MANAGEMENT DEVICES
SENSORS AND ACTUATORS
SHROUDS, BAFFLES AND DEFLECTORS
SPARK PLUGS
SPRING LOCKS
Standards as part of the inspection process and for communicating
their findings to their customers.
The Motorist Assurance Program continues to work
cooperatively and proactively with government agencies and consumer
groups toward solutions that both benefit the customer and are
mutually acceptable to both regulators and industry. We maintain the
belief that industry must retain control over how we conduct our
business, and we must be viewed as part of the solution and not part
of the problem. Meetings with state and other government officials
(and their representatives), concerned with auto repair and/or
consumer protection, are conducted. Feedback from these sessions is
brought back to the association, and the program adjusted as needed.
To assure auto repair customers recourse if they were not
satisfied with a repair transaction, the Motorist Assurance Program
offers mediation and arbitration through MAP/BBB-CARE and other non-
profit organizations. MAP conducted pilot programs in twelve states
before announcing the program nationally in October, 1998. During the
pilots, participating repair shops demonstrated their adherence to the
Pledge and Standards and agreed to follow the UICS in communicating
the results of their inspection to their customers. To put some
"teeth" in the program, an accreditation requirement for shops was
initiated. The requirements are stringent, and a self-policing method
has been incorporated which includes the "mystery shopping" of
outlets.
We welcome you to join us as we continue our outreach... with
your support, both the automotive repair industry and your customers
will reap the benefits. Please visit MAP at our Internet site www.
motorist.org or contact us at:
1444 I Street, NW Suite 700
Washington, DC 20005
Phone (202) 712-9042 Fax (202) 216-9646
January 1999
MAP UNIFORM INSPECTION GENERAL GUIDELINES
OVERVIEW OF SERVICE REQUIREMENTS AND SUGGESTIONS
It is MAP policy that all exhaust, brake, steering,
suspension, wheel alignment, drive-line, engine performance and
maintenance, and heating, ventilation and air conditioning, and
electrical services be offered and performed under the standards and
procedures specified in these sections.
Before any service is performed on a vehicle, an inspection
of the appropriate system must be performed. The results of this
inspection must be explained to the customer and documented on an
inspection form. The condition of the vehicle and its components will
indicate what services/part replacements may be "Required" or
"Suggested". In addition, suggestions may be made to satisfy the
requests expressed by the customer.
When a component is suggested or required to be repaired or
replaced, the decision to repair or replace must be made in the
customer's best interest, and at his or her choice given the options
available.
This section lists the various parts and conditions that
indicate a required or suggested service or part replacement.
Although this list is extensive, it is not fully inclusive. In
addition to this list, a technician may make a suggestion. However,
any suggestions must be based on substantial and informed experience,
or the vehicle manufacturer's recommended service interval and must be
documented.
Some conditions indicate that service or part replacement is
Terminal broken ......... A .. Require repair or replacement.
Terminal burned, affecting
performance ............ A ........... (1) Require repair or
replacement.
Terminal burned, not
affecting performance .. 2 .. Suggest repair or replacement.
Terminal corroded,
affecting performance .. A .. Require repair or replacement.
Terminal corroded, not
affecting performance .. 2 .. Suggest repair or replacement.
Terminal loose, affecting
performance ............ B .. Require repair or replacement.
Terminal loose, not
affecting performance .. 1 .. Suggest repair or replacement.
Threads damaged ......... A .. Require repair or replacement.
Threads stripped (threads
missing) ............... A ............ Require replacement.
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) - Determine cause and correct prior to repair or
replacement of part.
( 2) - Determine source of contamination, such as engine coolant,
fuel, metal particles, or water. Require repair or
replacement.
( 3) - Inoperative includes intermittent operation or out of
OEM specification. Some components may be serviceable;
check for accepted cleaning procedure.
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IGNITION BOOTS
See
IGNITION WIRES, BOOTS, COIL TOWERS AND TERMINALS (SECONDARY) .
IGNITION COIL TOWERS
See
IGNITION WIRES, BOOTS, COIL TOWERS AND TERMINALS (SECONDARY) .
IGNITION COILS
IGNITION COIL INSPECTION \
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Condition Code Procedure
Arcing .................. A ............ Require replacement.
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.
Connector broken ........ A .. Require repair or replacement.
Connector (Weatherpack
type) leaking .......... A .. Require repair or replacement.
Connector melted ........ A ........... ( 1) Require repair or
Connector missing ....... A ................. Require repair.
Contaminated ............ A ........... (3) Require repair or
replacement.
Leaking ................. A .. Require repair or replacement.
Malfunctioning .......... A ........... ( 4) Require repair or
replacement.
Missing ................. C ............ Require replacement.
Terminal broken ......... A .. Require repair or replacement.
Terminal burned, affecting
performance ............ A ........... ( 2) Require repair or
replacement.
Terminal burned, not
affecting performance .. 2 .. Suggest repair or replacement.
Terminal corroded,
affecting performance .. A .. Require repair or replacement.
Terminal corroded, not
affecting performance .. 2 .. Suggest repair or replacement.
Terminal loose, affecting
performance ............ B .. Require repair or replacement.
Terminal loose, not
affecting performance .. 1 .. Suggest repair or replacement.
Threads damaged ......... A .. Require repair or replacement.
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) - Includes inoperative, intermittent operation, or failure to
perform all functions.
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IGNITION SWITCHES
See SWITCHES.
IGNITION TERMINALS
See
IGNITION WIRES, BOOTS, COIL TOWERS AND TERMINALS (SECONDARY) .
IGNITION WIRES, BOOTS, COIL TOWERS AND TERMINALS (SECONDARY)
NOTE: You are not required to replace ignition wires in sets.
However, you may suggest replacement of the entire
secondary wire set for preventive maintenance.
IGNITION WIRE, BOOT, COIL TOWER AND TERMINAL (SECONDARY) INSPECTION
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Condition Code Procedure
Application incorrect ... B ............ Require replacement.
Attaching hardware
broken ................. A ... Require repair or replacement
of hardware.