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ENGINE CONTROL SYSTEMEC-129
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EC-130
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JCBWM2105GB
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![INFINITI QX56 2011 Factory Service Manual
FUEL PRESSUREEC-153
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FUEL PRESSURE
Work ProcedureINFOID:0000000006217756
FUEL PRESSURE RELEASE
WITH CONSULT-III
1. Turn ignition switch O INFINITI QX56 2011 Factory Service Manual
FUEL PRESSUREEC-153
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FUEL PRESSURE
Work ProcedureINFOID:0000000006217756
FUEL PRESSURE RELEASE
WITH CONSULT-III
1. Turn ignition switch O](/manual-img/42/57033/w960_57033-2176.png)
FUEL PRESSUREEC-153
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FUEL PRESSURE
Work ProcedureINFOID:0000000006217756
FUEL PRESSURE RELEASE
WITH CONSULT-III
1. Turn ignition switch ON.
2. Perform “FUEL PRESSURE RELEASE” in
“WORK SUPPORT” mode with CONSULT-III.
3. Start engine.
4. After engine stalls, crank it two or three times to release all fuel pressure.
5. Turn ignition switch OFF.
WITHOUT CONSULT-III
1. Remove fuel pump fuse in IPDM E/R. NOTE:
For the fuse number, refer to EC-114, "
Wiring Diagram".
For the fuse arrangement, refer to PG-143, "
Fuse, Connector and Terminal Arrangement".
2. Start engine.
3. After engine stalls, crank it two or three times to release all fuel pressure.
4. Turn ignition switch OFF.
5. Reinstall fuel pump fuse after servicing fuel system.
LOW FUEL PRESSURE CHECK
CAUTION:
Before disconnecting fuel line, release fuel pressure from fuel line to eliminate danger.
The fuel hose connection method used when taking fuel pressure check must not be used for other
purposes.
Do not perform fuel pressure check with electrical syst ems operating (i.e. lights, rear defogger, A/C,
etc.) Fuel pressure gauge may indicate false readin gs due to varying engine load and changes in
manifold vacuum.
NOTE:
Prepare pans or saucers under the disconnected fuel line because the fuel may spill out.
1. Release fuel pressure to zero.
2. Prepare fuel hose for fuel pressure check (B) and fuel tube adapter [SST (KV10118400)] (D), then connect fuel pressure
gauge (A).
CAUTION:
Use suitable fuel hose for fuel pressure check (genuine
NISSAN fuel hose without quick connector).
To avoid unnecessary force or tension to hose, use mod-
erately long fuel hose for fuel pressure check.
Do not use the fuel hose for checking fuel pressure with damage or cracks on it.
Use Pressure Gauge to check fuel pressure.
3. Disconnect fuel feed hose from fuel tube. Refer to EM-43, "
Exploded View".
CAUTION:
Do not twist or kink fuel hose because it is plastic hose.
To quick connector
To fuel tube (engine side)
C : Hose clamp
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![INFINITI QX56 2011 Factory Service Manual
P0420, P0430 THREE WAY CATALYST FUNCTIONEC-309
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Diagnosis ProcedureINFOID:0000000006217853
1.CHECK EXHAUST SYSTEM
Visually check exha INFINITI QX56 2011 Factory Service Manual
P0420, P0430 THREE WAY CATALYST FUNCTIONEC-309
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Diagnosis ProcedureINFOID:0000000006217853
1.CHECK EXHAUST SYSTEM
Visually check exha](/manual-img/42/57033/w960_57033-2332.png)
P0420, P0430 THREE WAY CATALYST FUNCTIONEC-309
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Diagnosis ProcedureINFOID:0000000006217853
1.CHECK EXHAUST SYSTEM
Visually check exhaust tubes and muffler for dents.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace malfunctioning part.
2.CHECK EXHAUST GAS LEAKAGE
1. Start engine and run it at idle.
2. Listen for an exhaust gas leakage before the three way catalyst (manifold).
Is exhaust gas leakage detected?
YES >> Repair or replace malfunctioning part.
NO >> GO TO 3.
3.CHECK INTAKE AIR LEAKAGE
Listen for an intake air leakage after the mass air flow sensor.
Is intake air leakage detected?
YES >> Repair or replace malfunctioning part.
NO >> GO TO 4.
4.CHECK IDLE SPEED AND IGNITION TIMING
Check idle speed and ignition timing.
For procedure, refer to EC-530, "
Inspection" and EC-531, "Inspection".
For specification, refer to EC-538, "
Idle Speed" and EC-538, "Ignition Timing".
Is the inspection result normal?
YES >> GO TO 5.
NO >> Follow the EC-139, "
Work Procedure".
5.CHECK FUEL INJECTORS
Refer to EC-498, "
Component Function Check".
Is the inspection result normal?
YES >> GO TO 6.
NO >> Perform EC-498, "
Diagnosis Procedure".
6.CHECK FUNCTION OF IGNITION COIL-I
CAUTION:
Perform the following procedure in a place with no combustible objects and good ventilation.
1. Turn ignition switch OFF.
2. Remove fuel pump fuse in IPDM E/R to release fuel pressure.
NOTE:
For the fuse number, refer to EC-114, "
Wiring Diagram".
For the fuse arrangement, refer to PG-140, "
Fuse, Connector and Terminal Arrangement".
Do not use CONSULT-III to release fuel pressure, or fuel pressure applies again during the following
procedure.
3. Start engine.
4. After engine stalls, crank it 2 or 3 times to release all fuel pressure.
5. Turn ignition switch OFF.
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