Mitsubishi Eclipse. Technical Information Manual (1994) — part 8

ENGINE <NON-TURBO> Intake and Exhaust

INTAKE AND EXHAUST

INTAKE MANIFOLD AND EXHAUST MANIFOLD

The intake manifold is a two-piece aluminum casting,

The exhaust manifold is made of nodular cast iron

attached to the cylinder head with six bolts and

for strength and high temperatures.

two studs. This long branch fan design enhances

low and

torque.

EXHAUST PIPE

The exhaust pipe consists of three parts: a front

transmission from the exhaust system to the body.

pipe, a center pipe, and a main muffler. It is mounted

A large main muffler, sub muffler and pre-muff ler

on the body via rubber hangers to minimize vibration

ensure reduced exhaust noise.

CONSTRUCTION

Flexible pipe

ted oxygen sensor

Pre-muff ler

Sub muffler

Heated oxygen sensor

Heated oxygen sensor

ENGINE <NON-TURBO> Fuel System

FUEL SYSTEM

The fuel system for 420A engine consists of

magnetic fuel injectors, a fuel rail, a fuel pressure

FUEL FLOW DIAGRAM

regulator, an electric motor-driven fuel pump, fuel

filter and fuel tank.

CONFIGURATION DIAGRAM

Fuel cut-off

valve assembly

Evaporative

emission
canister

Fuel pressure regulator

Fuel pump assembly

tank

Fuel rail

Fuel filter

ENGINE <NON-TURBO> Fuel System

FUEL TANK

The fuel tank is made of steel and is arranged under
the rear seat floor for higher safety. The fuel tank

has an internally mounted fuel pump assembly and

fuel gauge unit. In addition, a fuel cut-off valve

sembly is standard equipment on all vehicles. The
fuel cut-off valve assembly prevents outflow of fuel

even when the vehicle rolls over, assuring a higher
measure of safety.

Fuel

ENGINE <NON-TURBO> Control System

CONTROL SYSTEM

GENERAL INFORMATION

The fuel system for the 2.0 liter DOHC engine utilizes
sequential multi-port fuel injection to deliver precise
amounts of fuel to the intake manifold.

Basic injector duration is controlled by a combination
of signals from the front oxygen sensor and an air
density signal from a MAP sensor.

This vehicle uses a direct ignition system, eliminating
the need for a distributor. Ignition and fuel injector

operation are controlled by a new power-train control
module (PCM) which reviews inputs from a number
of sensors. The PCM provides outputs to fuel and
ignition system components to promote the most
efficient operation possible. The vehicle includes
a catalytic converter and sophisticated emissions
system diagnostic process (OBD II) to ensure that
emissions meet clean air regulations.

Major differences from the 1994 4G63 2.0 liter DOHC engine are as follows:

Major difference

Fast idle air valve is not equipped.

Remarks

On Mitsubishi manufactured engines, a fast idle air valve
is equipped in the throttle body.

Closed throttle position switch is not equipped.

Speed adjusting screw is not equipped.

Fixed SAS is fixed at the production line.

Throttle position sensor is fixed to the throttle body at
the production line.

Basic idle speed is not adjustable.

Fixed SAS is not equipped.

Throttle position sensor is not adjustable.

Camshaft position sensor waveform is different from the

A hall effect sensor is used, however, the construction of

current one.

the sensor is different.

Crankshaft position sensor waveform and its detection

A same Hall effect sensor is used, however, the

method are different from those current ones.

construction of the sensor is different.

On vehicles with automatic transaxle, vehicle speed
sensor signal is input from TCM.

Ignition switch-ST (cranking) signal input is not

PCM judges as engine cranking when the engine speed

vided .

is low.

MFI relay (ASD relay) and fuel pump relay are

Currently, these two are combined into one relay.

provided.

Generator generating voltage is controlled by PCM.

Currently, it is controlled by the voltage regulator built in
the generator.

Tachometer is controlled by PCM.

Charging system indicator lamp is controlled by PCM.

Control of the indicator/warning lamps (just after turning
ON the ignition switch) is performed by PCM.

Pulsed secondary air injection is controlled by PCM.

Data transmission system between PCM and TCM is

different from the current one.

Battery temperature sensor is built in PCM.

PCM is

mounted in the engine compartment.