Mitsubishi Montero (1998+). Manual - part 176

 leaking)  ...............  A  ............  Require replacement.

Sound quality

 unsatisfactory  .........  2  ..  Suggest replacement to address

                                    customer need and/or request.

Split (exhaust leaking)  .  A  ............  Require replacement.

Weak due to corrosion, but

 no leaks present  .......  1  ............  Suggest replacement.

F - BASIC TESTING 

1998 Mitsubishi Montero

         1998 ENGINE PERFORMANCE

         Mitsubishi - Basic Diagnostic Procedures

         Diamante, Eclipse, Galant, Mirage, Montero, Montero Sport,

         3000GT

         INTRODUCTION

         The following diagnostic steps will help prevent overlooking

a simple problem. This is also where to begin diagnosis for a no-start

condition. The first step in diagnosing any driveability problem is

verifying the customer’s complaint with a test drive under the

conditions the problem reportedly occurred.

         Before entering self-diagnostics, perform a careful and

complete visual inspection. Most engine control problems result from

mechanical breakdowns, poor electrical connections or

damaged/misrouted vacuum hoses. Before condemning the computerized

system, perform each test listed in this article.

NOTE:    Perform all voltage tests with a Digital Volt-Ohmmeter

         (DVOM) with a minimum 10-megohm input impedance, unless

         stated otherwise in test procedure.

         PRELIMINARY INSPECTION & ADJUSTMENTS

         VISUAL INSPECTION

         Visually inspect all electrical wiring, looking for chafed,

stretched, cut or pinched wiring. Ensure electrical connectors fit

tightly and are not corroded. Ensure vacuum hoses are properly routed

and are not pinched or cut. See M - VACUUM DIAGRAMS article to verify

routing and connections (if necessary). Inspect air induction system

for possible vacuum leaks.

         MECHANICAL INSPECTION

         Compression

         Check engine mechanical condition with a compression gauge,

vacuum gauge, or an engine analyzer. See engine analyzer manual for

specific instructions.

WARNING: DO NOT use ignition switch during compression tests on fuel

         injected vehicles. Use a remote starter to crank engine.

         Fuel injectors on many models are triggered by ignition

         switch during cranking mode, which can create a fire hazard

         or contaminate the engine’s oiling system.

         Check engine compression with engine at normal operating

temperature, all spark plugs removed and throttle wide open. See

COMPRESSION SPECIFICATIONS table.

COMPRESSION SPECIFICATIONS TABLE

Application (1)                                Specification

Compression Ratio

  1.5L (VIN A)  .....................................  9.0:1

  1.8L (VIN C)  .....................................  9.5:1

  2.0L

    (VIN F)  ........................................  8.5:1

    (VIN Y)  ........................................  9.6:1

  2.4L (VIN G)  .....................................  9.5:1

  3.0L

    (VIN H)  ........................................  8.9:1

    (VIN J)  .......................................  10.0:1

    (VIN K)  ........................................  8.0:1

    (VIN P)  ........................................  9.0:1

  3.5L (VIN M & P)  .................................  9.0:1

Compression Pressure

  1.5L (VIN A)  .....................  192 psi (13.4 kg/cm



)

  1.8L (VIN C)  .....................  199 psi (13.9 kg/cm



)

  2.0L (VIN F)  .....................  178 psi (12.5 kg/cm



)

  2.0L (VIN Y)  ............  170-225 psi (11.7-15.5 kg/cm



)

  2.4L (VIN G)  .....................  192 psi (13.4 kg/cm



)

  3.0L

    (VIN H & P)  ....................  171 psi (12.0 kg/cm



)

    (VIN J)  ........................  185 psi (13.0 kg/cm



)

    (VIN K)  ........................  156 psi (10.9 kg/cm



)

  3.5L (VIN M & P)  .................  171 psi (12.0 kg/cm



)

Maximum Variation

 Between Cylinders (2)  ...............  14 psi (1.0 kg/cm



)

(1) - See A - ENGINE/VIN ID article for VIN information.

(2) - On Eclipse 2.0L non-turbo engine, maximum variation

      between cylinders is 25%.

         Exhaust System Backpressure

         The exhaust system can be tested with a vacuum or pressure

gauge. If using a pressure gauge, remove HO2S or air injection check

valve (if equipped). Connect a 0-5 psi pressure gauge and run engine

at 2500 RPM. If exhaust system backpressure is greater than 2 psi,

exhaust system or catalytic converter is plugged.

         If using a vacuum gauge, connect vacuum gauge hose to intake

manifold vacuum port. Start engine. Observe vacuum gauge. Open

throttle part way and hold steady. If vacuum gauge indication slowly

drops after stabilizing, inspect exhaust system for restriction.

         FUEL SYSTEM

         * PLEASE READ THIS FIRST *

WARNING: ALWAYS relieve fuel pressure before disconnecting any fuel

         injection-related component. DO NOT allow fuel to contact

         engine or electrical components.

         RELIEVING FUEL PRESSURE

         1) On Diamante, disconnect fuel pump harness connector at

fuel tank from underneath vehicle. On Montero and Montero Sport,

remove cargo compartment carpet, remove access plate and disconnect

fuel pump harness connector. On all other models, remove rear seat

cushion, remove access plate (if required) and disconnect fuel pump

harness connector.

         2) On all models, start engine. Let engine run until it

stops. Turn ignition off. Disconnect negative battery cable. Connect

fuel pump harness connector. Install rear seat and/or carpet as

necessary.

WARNING: Before disconnecting high pressure fuel hose at fuel

         delivery pipe, cover fuel hose connection with a rag. Some

         residual fuel pressure may still be in system.

         FUEL PRESSURE

         1) Relieve fuel pressure. See RELIEVING FUEL PRESSURE. On

models with fuel rail service valve, connect fuel pressure gauge to

fuel rail. On models without fuel rail service valve, disconnect high

pressure fuel inlet line at fuel rail. Remove throttle body bracket

(if necessary). Connect fuel pressure gauge with adapter between fuel

rail and high pressure fuel inlet line. See  Fig. 1.

Fig. 1:  Installing Fuel Pressure Tester (Typical)

Courtesy of Mitsubishi Motor Sales of America

         2) On Eclipse 2.0L non-turbo and Montero Sport, use scan tool

to operate fuel pump. On all other models, operate fuel pump by

connecting battery voltage to fuel pump test terminal. See

FUEL PUMP TEST TERMINAL LOCATION table. Ensure no fuel leaks are

present. Disconnect battery voltage from fuel pump test terminal.

FUEL PUMP TEST TERMINAL LOCATION TABLE