Mitsubishi Outlander GS45X. Manual - part 644

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-399

STEP 19. Test the OBD-II drive cycle.
(1) Carry out a test drive with the drive cycle pattern. Refer to 

Diagnostic Function 

− OBD-II Drive Cycle − Pattern 23 

P.13A-11

.

(2) Check the diagnostic trouble code (DTC).
Q: Is DTC P0365 set?

YES : Retry the troubleshooting.
NO :  The inspection is complete.

DTC P0401: Exhaust Gas Recirculation Flow Insufficient Detected

.

TECHNICAL DESCRIPTION

• When the EGR valve (stepper motor) is actuated 

from the fully closed position toward the open 
position while the engine is running, EGR gas 
flows.

• The ECM checks how the EGR gas flow signal 

changes.

.

DESCRIPTIONS OF MONITOR METHODS

Small manifold pressure change during exhaust gas 

recirculation (EGR) operation from closed to 
open.

.

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)

• EGR stepper motor monitor

Sensor (The sensor below is determined to be 

normal)

• Mass airflow sensor

• Engine coolant temperature sensor

• Intake air temperature sensor

• Barometric pressure sensor

• Accelerator pedal position sensor

• Manifold absolute pressure sensor

.

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-400

DTC SET CONDITIONS
Logic Flow Chart

.

Check Conditions

• At least 20 seconds have passed since the last 

monitor was complete.

• Engine coolant temperature is higher than 76°C 

(169

°F).

• Engine speed is at between 1,125 and 2,500 

r/min.

• Intake air temperature is higher than −10°C 

(14

°F).

• Barometric pressure is higher than 76 kPa (22.4 

in.Hg).

• Fuel is being shut off.

• Vehicle speed is 30 km/h (19 mph) or more.

• At least 90 seconds have passed since manifold 

absolute pressure sensor output voltage fluctu-
ated 1.5 volts or more.

• Battery positive voltage is higher than 10.3 volts.

• Accelerator pedal is closed.

• Volumetric efficiency is lower than 24 percent.

Start

End

No

No

No

Yes

Yes

Yes

Malfunction

Good

Monitoring

conditions

Measure manifold

pressure (P1)

Measure manifold

pressure (P2)

EGR valve open

P2 - P1 < P0 *

Specified

times

AK604336

P0 : Threshold value

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-401

• The ECM monitors for this condition for 3 cycles 

of 1.8 seconds each during the drive cycle.

Judgement Criterion

• When the EGR valve opens to the prescribed 

opening, when intake manifold pressure fluctua-
tion width is lower than 2.5 kPa (0.74 in.Hg).

.

OBD-II DRIVE CYCLE PATTERN

Refer to Diagnostic Function 

− OBD-II Drive Cycle − 

Pattern 3 

P.13A-11

.

.

TROUBLESHOOTING HINTS (The most 
likely causes for this code to be set are: )

• Contaminated EGR valve and EGR passage.

• ECM failed

DIAGNOSIS

STEP 1. Check the EGR system
Refer to GROUP 17, Emission Control System 

− Exhaust Gas 

Recirculation (EGR) System 

− General Information 

P.17-80

.

Q: Are there any abnormalities?

YES : Repair it. Then go to Step 3.
NO :  Go to Step 2.

STEP 2. Check the EGR valve contamination and the EGR 
passage contamination.
Q: Are the EGR valve and the EGR passage clogged?

YES : Repair the EGR valve and the EGR passage 

contamination.

NO :  Go to Step 3.

STEP 3. Test the OBD-II drive cycle.
(1) Carry out a test drive with the drive cycle pattern. Refer to 

Diagnostic Function 

− OBD-II Drive Cycle − Pattern 3 

P.13A-11

.

(2) Check the diagnostic trouble code (DTC).
Q: Is DTC P0401 set?

YES : Retry the troubleshooting.
NO :  The inspection is complete.

DTC P0420: Warm Up Catalyst Efficiency Below Threshold

.

TECHNICAL DESCRIPTION

• The signal from the heated oxygen sensor (rear) 

differs from the linear air-fuel ratio sensor, 
because the catalytic converter purifies exhaust 
gas. When the catalytic converter has deterio-
rated, the signal from the linear air-fuel ratio sen-
sor becomes similar to the heated oxygen sensor 
(rear).

• The ECM compares the output of the linear 

air-fuel ratio sensor and heated oxygen sensor 
(rear) signals.

.

DESCRIPTIONS OF MONITOR METHODS

Linear air-fuel ratio sensor and heated oxygen sen-

sor (rear) rich/lean switching frequencies are 
nearly equal.

.

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)

• Linear air-fuel ratio sensor monitor

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-402

• Heated oxygen sensor (rear) monitor

• Linear air-fuel ratio sensor heater monitor

• Heated oxygen sensor (rear) heater monitor

• Heated oxygen sensor offset voltage monitor

• Misfire monitor

• Fuel system monitor

• Heated oxygen sensor (rear) feedback control 

system

Sensor (The sensor below is determined to be 

normal)

• Mass airflow sensor

• Engine coolant temperature sensor

• Intake air temperature sensor

• Barometric pressure sensor

• Throttle position sensor

• Accelerator pedal position sensor

.

DTC SET CONDITIONS
Logic Flow Chart

.

Check Conditions

• Engine speed is lower than 3,000 r/min.

• Accelerator pedal is depressed.

• Mass airflow is between 10 and 45 g/sec.

• More than 3 seconds have elapsed after the 

above-mentioned three conditions have been 
met.

• Intake air temperature is higher than −10°C 

(14

°F).

• Barometric pressure is higher than 76 kPa (22.4 

in.Hg).

• Under the closed loop air/fuel ratio control.

• Vehicle speed is 1.5 km/h (1.0 mph) or more.

• The ECM monitors the maximum 3 times per 

drive cycle under these conditions.

• Short-term fuel trim is higher than −25 percent 

and lower than +25 percent.

• The cumulative mass airflow is higher than 1,741 

g.

• The linear air-fuel ratio sensor rich/lean switching 

frequency is more than 8 times.

Judgement Criterion

• When the monitoring for 10 seconds is carried 

out 5 times, the frequency ratio of heated oxygen 
sensor (rear) and linear air-fuel ratio sensor sig-
nals is the specified value or more.
NOTE: The specified value varies depending on 
the average air flow rate.

.

Start

Monitoring

conditions

Malfunction

Good

End

No

No

Yes

Yes

Rf > R0

Calculate average frequency

ratio (Rf = Fr/Ff) of specified times

R0: Average threshold value

AK604337