Nissan Sentra Service Manual: Fuel injector

Component Function Check

1.INSPECTION START

Turn ignition switch to START.

Is any cylinder ignited? YES >> GO TO 2.

NO >> Proceed to EC-450, "Diagnosis Procedure".

2.CHECK FUEL INJECTOR FUNCTION

With CONSULT

1. Start engine.
2. Perform “POWER BALANCE” in “ACTIVE TEST” mode of “ENGINE” using CONSULT.
3. Check that each circuit produces a momentary engine speed drop

Without CONSULT

1. Let engine idle.
2. Listen to each fuel injector operating sound.

Clicking noise should be heard.

Is the inspection result normal? YES >> INSPECTION END

NO >> Proceed to EC-450, "Diagnosis Procedure".

Diagnosis Procedure

1.CHECK FUSE

1. Turn ignition switch OFF.
2. Pull out #52 fuse and check that the fuse is not fusing.

Is the inspection result normal? YES >> GO TO 2.

NO >> Replace the fuse after repairing the applicable circuit.

2.CHECK FUEL INJECTOR POWER SUPPLY

1. Insert the fuse which pulled out.
2. Disconnect fuel injector harness connector.
3. Turn ignition switch ON.
4. Check the voltage between fuel injector harness connector and ground.

Is the inspection result normal? YES >> GO TO 4.

NO >> GO TO 3.

3.CHECK FUEL INJECTOR POWER SUPPLY CIRCUIT

1. Turn ignition switch OFF.
2. Disconnect IPDM E/R harness connector.
3. Check the continuity between fuel injector harness connector and IPDM E/R harness connector

4. Also check harness for short to ground.

Is the inspection result normal? YES >> Check intermittent incident. Refer to GI-39, "Intermittent Incident".

NO >> Repair or replace error-detected parts.

4.CHECK FUEL INJECTOR CONTROL CIRCUIT

1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between fuel injector harness connector and ECM harness connector.

4. Also check harness for short to ground and to power.

Is the inspection result normal? YES >> GO TO 5.

NO >> Repair or replace error-detected parts

5.CHECK FUEL INJECTOR

Check the fuel injector. Refer to EC-451, "Component Inspection (Fuel Injector)".

Is the inspection result normal? YES >> Check intermittent incident. Refer to GI-39, "Intermittent Incident" NO >> Replace malfunctioning fuel injector. Refer to EM-40, "Removal and Installation".

Component Inspection (Fuel Injector)

1.CHECK FUEL INJECTOR

1. Turn ignition switch OFF.
2. Disconnect fuel injector harness connector.
3. Check resistance between fuel injector terminals as per the following.

Is the inspection result normal? YES >> INSPECTION END

NO >> Replace malfunctioning fuel injector. Refer to EM-40, "Removal and Installation"