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Mitsubishi Eclipse. Manual - part 497

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-531

DTC SET CONDITIONS

Logic Flow Chart

Check Conditions

• Engine speed is between 440 and 6,000 r/min.

• Engine coolant temperature is higher than −10°C

(14

°F).

• Intake air temperature is higher than −10°C

(14

°F).

• Barometric pressure is higher than 76 kPa (11

psi).

• Volumetric efficiency is at between 30 and 60

percent.

• Adaptive learning is complete for the vane which

generates a crankshaft position signal.

• While the engine is running, excluding gear shift-

ing, deceleration, sudden acceleration/decelera-
tion and A/C compressor switching.

START

MONITORING

CONDITIONS

CALCULATE CRANKSHAFT

ANGULAR ACCELERATION (An)

< TH

(Ne, v)

MISFIRE

CALCULATE PERCENT MISFIRE (R

)

END

YES

GOOD

WITHIN 1000rev

> SPECIFIED VALUE

MALFUNCTION

(EXCEED STD ×1.5)

GOOD

MALFUNCTION

(DAMAGE THE CAT.)

GOOD

> TH

(Ne, v)

CALCULATE PERCENT MISFIRE (R

)

WITHIN 200rev

Ne: ENGINE SPEED
v: VOLUMETRIC EFFICIENCY

AK302602

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-532

• The throttle deviation is −0.059 v/10 ms to +0.059

v/10 ms.

Judgement Criteria (change in the angular accel-

eration of the crankshaft is used for misfire
detection).

• Misfire has occurred more frequently than

allowed during the last 200 revolutions [when the
catalyst temperature is higher than 950

°C

(1742

°F)].

• Misfire has occurred in 20 or more of the last

1,000 revolutions (corresponding to 1.5 times the
limit of emission standard).

OBD-ll DRIVE CYCLE PATTERN
Refer to Diagnostic Function

− OBD-ll Drive Cycle −

Procedure 6

− Other Monitor

P.13B-7

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

• Ignition system related part (s) failed.

• Poor crankshaft position sensor.

• Incorrect air/fuel ratio.

• Low compression pressure.

• Skipping of timing belt teeth.

• EGR system and EGR valve failed.

• ECM failed. <M/T>

• PCM failed. <A/T>

• Injector faild.

• Spark plug faild.

• Harness damage in injector circuit, or conector

damage.

DIAGNOSIS

Required Special Tools:

• MB991958: Scan Tool (MUT-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991911: Main Harness B

STEP 1. Using scan tool MB991958, check data list item 22:
Crankshaft Position Sensor.

CAUTION

To prevent damage to scan tool MB991958, always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
(1) Connect scan tool MB991958 to the data link connector.
(2) Start the engine and run at idle.
(3) Set scan tool MB991958 to the data reading mode for item

22, Crankshaft Position Sensor.

(4) Check the waveform of the crankshaft position sensor while

keeping the engine speed constant.

• The pulse width should be constant.

(5) Turn the ignition switch to "LOCK" (OFF) position.
Q: Is the sensor operating properly?

YES : Go to Step 2.
NO : Refer to DTC P0335

− Crankshaft Position Sensor

Circuit Malfunction

P.13B-557

AK300810

MB991911

16-PIN

MB991827

MB991824

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-533

STEP 2. Using scan tool MB991958, check data list item 81:
Long-Term Fuel Trim (trim) Bank 1.
(1) Start the engine and run at idle.
(2) Set scan tool MB991958 to the data reading mode for item

81, Long-Term Fuel Trim (trim) Bank 1.

• The fuel trim should be between −12.5 and +12.5 when

the load is 2,500 r/min (during closed loop) after the
engine is warmed.

(3) Turn the ignition switch to "LOCK" (OFF) position.
Q: Is the specification normal?

YES : Go to Step 3.
NO : Refer to DTC P0171

− System too Lean (bank 1)

P.13B-445

, DTC P0172

− System too Rich (bank 1)

P.13B-455

, DTC P0174

− System too Lean (bank 2)

P.13B-461

, DTC P0175

− System too Rich (bank 2)

P.13B-470

STEP 3. Using scan tool MB991958, check data list item 82:
Short-Term Fuel Trim (trim) Bank 1.
(1) Start the engine and run at idle.
(2) Set scan tool MB991958 to the data reading mode for item

82, Short-Term Fuel Trim (trim) Bank 1.

• The fuel trim should be between −25 and +25 when the

load is 2,500 r/min (during closed loop) after the engine
is warmed.

(3) Turn the ignition switch to "LOCK" (OFF) position.
Q: Is the specification normal?

YES : Go to Step 4.
NO : Refer to DTC P0171

− System too Lean (bank 1)

P.13B-445

, DTC P0172

− System too Rich (bank 1)

P.13B-455

, DTC P0174

− System too Lean (bank 2)

P.13B-461

, DTC P0175

− System too Rich (bank 2)

P.13B-470

AK300810

MB991911

16-PIN

MB991827

MB991824

AK300810

MB991911

16-PIN

MB991827

MB991824

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-534

STEP 4. Check the ignition coil spark.
(1) Check each ignition coil spark.
(2) Remove the intake manifold.
(3) Remove the spark plug and connect to the spark plug

cable.

(4) Ground the spark plug side electrode securely.

• When the engine is cranked, the spark plug should

spark.

Q: Did it spark?

YES : Go to Step 7.
NO : Go to Step 5.

STEP 5. Check the spark plugs.

CAUTION

Do not attempt to adjust the gap of the platinum plug.
Cleaning of the platinum plug may result in damage to the
platinum tips. Therefore, if carbon deposits must be
removed, use a plug cleaner and complete cleaning within
20 seconds to protect the electrode. Do not use a wire
brush.
(1) Check the plug gap and replace if the limit is exceeded.

Standard value: 1.0

− 1.1 mm (0.039 − 0.043 inch)

Limit: 1.3 mm (0.051 inch)

Q: Is the plug gap at the standard value?

YES : Go to Step 6.
NO : Replace the faulty spark plug. Then go to Step 13.

STEP 6. Check the spark plug cable.
(1) Check the cap and coating for cracks.
(2) Measure the resistance.

Limit: maximum 22 k

Ω

Q: Is the resistance normal?

YES : Refer to INSPECTION PROCEDURE 33

− Ignition

Circuit System

P.13B-1053

NO : Replace the faulty spark plug cable. Then go to Step

13.

AKX00432

SPARK PLUG

AKX00383

PLATINUM
TIPS

AKX00382

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