Nissan X-Trail 32. Instruction — part 780
P0171 FUEL INJECTION SYSTEM FUNCTION
EC-249
< DTC/CIRCUIT DIAGNOSIS >
[MR20DD]
C
D
E
F
G
H
I
J
K
L
M
A
EC
N
P
O
>> GO TO 2.
2.
PERFORM DTC CONFIRMATION PROCEDURE-1
1.
Clear the mixture ratio self-learning value. Refer to
.
2.
Start engine.
Is it difficult to start engine?
YES
>> GO TO 3.
NO
>> GO TO 4.
3.
RESTART ENGINE
If it is difficult to start engine, the fuel injection system has a malfunction, too.
Crank engine while depressing accelerator pedal.
NOTE:
When depressing accelerator pedal three fourths (3/4) or more, the control system does not start the engine.
Do not depress accelerator pedal too much.
Does engine start?
YES
>> Proceed to
.
NO
>> Check exhaust and intake air leakage visually.
4.
PERFORM DTC CONFIRMATION PROCEDURE-2
1.
Keep engine idle for at least 10 minutes.
2.
Check 1st trip DTC.
Is 1st trip DTC detected?
YES
>> Proceed to
.
NO
>> GO TO 5.
5.
PERFORM DTC CONFIRMATION PROCEDURE-3
1.
Turn ignition switch OFF and wait at least 10 seconds.
2.
Start engine and Maintain the following conditions for at least 10 consecutive minutes. Hold the accelera-
tor pedal as steady as possible.
CAUTION:
Always drive vehicle at a safe speed.
3.
Check 1st trip DTC.
Is 1st trip DTC detected?
YES
>> Proceed to
.
NO-1
>> To check malfunction symptom before repair: Refer to
GI-44, "Intermittent Incident"
NO-2
>> Confirmation after repair: INSPECTION END
Diagnosis Procedure
INFOID:0000000010775158
1.
CHECK EXHAUST GAS LEAKAGE
1.
Start engine and run it at idle.
2.
Listen for an exhaust gas leakage before three way catalyst (manifold).
Is exhaust gas leakage detected?
Vehicle
speed
50 - 100 km/h (31 - 62 MPH)
PBIB1216E
EC-250
< DTC/CIRCUIT DIAGNOSIS >
[MR20DD]
P0171 FUEL INJECTION SYSTEM FUNCTION
YES
>> Repair or replace malfunctioning part.
NO
>> GO TO 2.
2.
CHECK FOR INTAKE AIR LEAKAGE
1.
Listen for an intake air leakage after the mass air flow sensor.
2.
Check PCV hose connection.
Is intake air leakage detected?
YES
>> Repair or replace malfunctioning part.
NO
>> GO TO 3.
3.
CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.
Turn ignition switch OFF.
2.
Disconnect corresponding A/F sensor 1 harness connector.
3.
Disconnect ECM harness connector.
4.
Check the continuity between A/F sensor 1 harness connector and ECM harness connector.
5.
Check the continuity between A/F sensor 1 harness connector and ground, or ECM harness connector
and ground.
6.
Also check harness for short to ground and short to power.
Is the inspection result normal?
YES
>> GO TO 4.
NO
>> Repair or replace malfunctioning part.
4.
CHECK FUEL PRESSURE
1.
Install all removed parts.
2.
Release fuel pressure to 0. Refer to
.
3.
Set a fuel pressure meter and check fuel pressure. Refer to
Is the inspection result normal?
YES
>> GO TO 6.
NO
>> GO TO 5.
5.
DETECT MALFUNCTIONING PART
Check fuel hoses and fuel tubes for clogging.
+
−
Continuity
A/F sensor 1
ECM
Connector
Terminal
Connector
Terminal
F27
1
F8
64
Existed
2
72
+
Ground
Continuity
A/F sensor 1
Connector
Terminal
F27
1
Ground
Not existed
2
+
Ground
Continuity
ECM
Connector
Terminal
F8
64
Ground
Not existed
72
At idle: 500 kPa (5.1 kg/cm
2
)
P0171 FUEL INJECTION SYSTEM FUNCTION
EC-251
< DTC/CIRCUIT DIAGNOSIS >
[MR20DD]
C
D
E
F
G
H
I
J
K
L
M
A
EC
N
P
O
Is the inspection result normal?
YES
>> Replace “fuel filter and fuel pump assembly”. Refer to
FL-12, "Removal and Installation"
.
NO
>> Repair or replace malfunctioning part.
6.
CHECK MASS AIR FLOW SENSOR
WITH CONSULT
1.
Install all removed parts.
2.
Start engine and warm it up to normal operating temperature.
3.
Check “MASS AIR FLOW” in “DATA MONITOR” mode with CONSULT.
*: Check for linear voltage rise in response to increase of engine speed.
WITHOUT CONSULT
1.
Install all removed parts.
2.
Start engine and warm it up to normal operating temperature.
3.
Check the voltage between ECM harness connector terminals under the following conditions.
*: Check for linear voltage rise in response to increase of engine speed.
Is the inspection result normal?
YES
>> GO TO 7.
NO
>> Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or
grounds. Refer to
7.
CHECK FUNCTION OF FUEL INJECTOR
WITH CONSULT
1.
Start engine.
2.
Perform “POWER BALANCE” in “ACTIVE TEST” mode with CONSULT.”
3.
Check that each circuit produces a momentary engine speed drop.
WITHOUT CONSULT
1.
Start engine and let it idle.
2.
Listen to each fuel injector operating sound.
Is the inspection result normal?
YES
>> GO TO 8.
NO
>> Perform trouble diagnosis for fuel injector and circuit,
.
8.
CHECK FUEL INJECTOR
Monitor item
Condition
Indication
A/F SEN1 (B1)
Ignition switch ON (Engine stopped.)
Approx. 0.4 V
Idle (Engine is warmed-up to normal op-
erating temperature.)
0.7 - 1.2 V
Idle to about 4,000 rpm
0.7 -1.2 V
→
2.4 V*
ECM
Condition
Voltage
Connector
+
–
Terminal
F7
28
20
Ignition switch ON (Engine stopped.)
Approx. 0.4 V
Idle (Engine is warmed-up to normal
operating temperature.)
0.7 -1.2 V
Idle to about 4,000 rpm
0.7 -1.2 V
→
2.4 V*
Clicking sound should
be heard.
PBIB3332E
EC-252
< DTC/CIRCUIT DIAGNOSIS >
[MR20DD]
P0171 FUEL INJECTION SYSTEM FUNCTION
1.
Turn ignition switch OFF.
2.
Confirm that the engine is cooled down and there are no fire hazards near the vehicle.
3.
Remove fuel tube assembly. Refer to
.
Keep fuel hose and all fuel injectors connected to fuel tube.
4.
The fuel injector harness connectors should remain connected.
5.
Disconnect all ignition coil harness connectors.
6.
Prepare pans or saucers under each fuel injector.
7.
Crank engine for about 3 seconds.
Is the inspection result normal?
YES
>> INSPECTION END
NO
>> Replace fuel injectors from which fuel does not spray
out evenly. Refer to
EM-48, "Removal and Installation"
.
Always replace O-ring with new ones.
Fuel should be sprayed evenly for each fuel injec-
tor.
PBIA8556J
Нет комментариевНе стесняйтесь поделиться с нами вашим ценным мнением.
Текст