Mitsubishi Galant 9G. Manual — part 649

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-38

SYMPTOM CHART

M1131151500760

CAUTION

During diagnosis, a DTC associated with other
system may be set when the ignition switch is
turned on with connector(s) disconnected. On
completion, confirm all systems for DTCs. If
DTCs are set, erase them all.

CAUTION

Disconnecting the battery cables or removing the
combination meter will erase the learned value of
the fuel gauge. To recover the learned value,
input a vehicle speed (by actually driving the
vehicle or inputting a simulated vehicle speed),
and stop the vehicle. This will complete the learn-
ing process.

.

NOTE: Check that the PCM ground circuit is normal
before checking for the cause of the problem.

TROUBLE SYMPTOMS

INSPECTION
PROCEDURE

REFERENCE PAGE

Communication
with scan tool is
impossible

Communication with all systems is not possible

1

P.13A-967

Communication with PCM only is not possible

2

P.13A-970

Malfunction
Indicator Lamp
(SERVICE
ENGINE SOON
or Check
Engine Lamp)
and related
parts

The Malfunction Indicator Lamp (SERVICE ENGINE
SOON or Check Engine Lamp) does not illuminate
right after the ignition switch is turned to the "ON"
position

3

P.13A-973

The Malfunction Indicator Lamp (SERVICE ENGINE
SOON or Check Engine Lamp) remains illuminated
and never goes out

4

P.13A-974

Starting

Cranks, won't start

5

P.13A-976

Starts up and dies

6

P.13A-981

Hard starting

7

P.13A-986

Idling stability
(improper
idling)

Unstable idle (rough idle, hunting)

8

P.13A-991

Idle speed is high (improper idle speed)

9

P.13A-995

Idle speed is low (improper idle speed)

10

P.13A-997

Idling stability
(engine stalls)

When the engine is cold, it stalls at idle (die out)

11

P.13A-999

When the engine is hot, it stalls at idle (die out)

12

P.13A-1002

The engine stalls when accelerating (pass out)

13

P.13A-1005

The engine stalls when decelerating

14

P.13A-1007

Driving

Hesitation, sag or stumble

15

P.13A-1009

Acceleration shock

16

P.13A-1013

Deceleration shock

17

P.13A-1014

Poor acceleration

18

P.13A-1015

Surge

19

P.13A-1018

Knocking

20

P.13A-1022

Dieseling (Run-on)

21

P.13A-1024

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-39

.

PROBLEM SYMPTOMS TABLE (FOR YOUR INFORMATION)

Too high CO and HC concentration when idling

22

P.13A-1024

IM240 test
failure

Transient, mass emission tailpipe test failure

23

P.13A-1027

Purge flow test of the evaporative emission canister
failure

24

P.13A-1034

Pressure test of the evaporative system failure

25

P.13A-1035

Generator output voltage is low (approximately 12.3 volts)

26

P.13A-1036

Fans (radiator fan, A/C condenser fan) are inoperative

27

P.13A-1040

Power supply system and ignition switch-IG system

28

P.13A-1043

Fuel pump system

29

P.13A-1054

Ignition switch-ST system and transmission range switch system

30

P.13A-1068

Ignition circuit system

31

P.13A-1073

A/C system

32

P.13A-1081

TROUBLE SYMPTOMS

INSPECTION
PROCEDURE

REFERENCE PAGE

ITEMS

SYMPTOM

At starting

Won't start

The starter cranks the engine, but there is no combustion within the
cylinders, and the engine won't start.

Starts up and
dies

The engine starts, but then engine soon stalls.

Hard starting

Engine starts after cranking a while.

Idling stability

Hunting

Engine speed doesn't remain constant; changes at idle.

Rough idle

Usually, a judgement can be based upon the movement of the
tachometer pointer, and the vibration transmitted to the steering wheel,
shift lever, body, etc.

Incorrect idle
speed

The engine doesn't idle at the correct speed.

Engine stall (die
out)

The engine stalls when the foot is taken from the accelerator pedal,
regardless of whether the vehicle is moving or not.

Engine stall
(pass out)

The engine stalls when the accelerator pedal is depressed.

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-40

At driving

Hesitation Sag

"Hesitation" is the delay in
response of the vehicle speed
(engine speed). This occurs when
the accelerator is depressed in
order to accelerate from the speed
at which the vehicle is now
traveling, or a temporary drop in
vehicle speed (engine speed)
during such acceleration.
Serious hesitation is called "sag".

Poor
acceleration

Poor acceleration is inability to obtain an acceleration corresponding to
the degree of throttle opening, even though acceleration is smooth.
Also the inability to reach maximum speed.

Stumble

Engine speed increase is delayed
when the accelerator pedal is
initially depressed for acceleration.

Shock

The feeling of a comparatively large impact or vibration when the
engine is accelerated or decelerated.

Surge

This is slight acceleration and deceleration feel usually felt during
steady, light throttle cruise. Most notable under light loads.

Knocking

A sharp sound during driving, which sounds like a hammer striking the
cylinder walls. It makes poor driveability.

At stopped

Run on
("Dieseling")

The condition in which the engine continues to run after the ignition
switch is turned to the "LOCK" (OFF) position. Also called "dieseling".

ITEMS

SYMPTOM

AKX01361

VEHICLE
SPEED

TIME

NORMAL

HESITATION

SAG

INITIAL
ACCELE-
RATOR
PEDAL
DEPRE-
SSION

AKX01361AB

AKX01362

VEHICLE
SPEED

TIME

NORMAL

STUMBLE

INITIAL
ACCEL-
ERATOR
PEDAL
DEP-
RESSION

IDLING

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-41

DIAGNOSTIC TROUBLE CODE PROCEDURES

DTC P0069: Abnormal Correlation Between Manifold Absolute Pressure Sensor And Barometric
Pressure Sensor

.

TECHNICAL DESCRIPTION

• The PCM detects abnormality in the sensor by

comparing the manifold absolute pressure sensor
output with the barometric pressure sensor out-
put.

.

DESCRIPTIONS OF MONITOR METHODS

The PCM compares the manifold absolute pressure

sensor output with the barometric pressure sen-
sor output while the engine control relay is in
"ON" position after the ignition switch is in
"LOCK" (OFF) position. When the difference
exceeds the specified value between them, the
PCM determines whether the manifold absolute
pressure sensor / the barometric pressure sensor
has malfunction or not.

.

MONITOR EXECUTION

Continuous

.

MONITOR EXECUTION CONDITIONS
(Other monitor and Sensor)

Other Monitor (There is no temporary DTC stored

in memory for the item monitored below)

• Not applicable

Sensor (The sensor below is determined to be

normal)

• Not applicable

.