Fuel Injector: Testing and Inspection
FUEL INJECTOR
Description
The fuel injector is a small, precise solenoid valve. When the ECM
supplies a ground to the fuel injector circuit, the coil in the fuel injector is energized. The energized coil pulls the ball valve back and allows fuel to flow through the fuel injector into the intake manifold.
The amount of fuel injected depends upon the injection pulse duration. Pulse duration is the length of time the fuel injector remains open. The ECM controls the injection pulse duration based on engine fuel needs.
Component Function Check
1. INSPECTION START
Turn ignition switch to START.
Are any cylinders ignited?
YES- GO TO 2.
NO- Go to "Diagnosis Procedure" .
2. CHECK FUEL INJECTOR FUNCTION
With CONSULT
1.Start engine.
2.Perform "POWER BALANCE" in "ACTIVE TEST" mode with CONSULT.
3.Make sure that each circuit produces a momentary engine speed drop.
Without CONSULT
1.Start engine.
2.Listen to each fuel injector operating sound.
Clicking sound should be heard.
Is the inspection result normal?
YES- INSPECTION END
NO- Go to "Diagnosis Procedure" .
Diagnosis Procedure
1. CHECK FUEL INJECTOR POWER SUPPLY CIRCUIT
1.Turn ignition switch OFF.
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 3.
NO- GO TO 2.
2. DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors E3, F1
- Harness connectors F10, F120
- IPDM E/R harness connector E7
- 10 A fuse (No. 44)
- Harness for open or short between fuel injector and fuse
- Repair open circuit, short to ground or short to power in harness or connectors.
3. CHECK FUEL INJECTOR OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
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 short to power.
Is the inspection result normal?
YES- GO TO 5.
NO- GO TO 4
4. DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors F10, F120
- Harness connectors F106, F107
- Harness for open or short between fuel injector and ECM
- Repair open circuit, short to ground or short to power in harness or connectors.
5. CHECK FUEL INJECTOR
Refer to "Component Inspection" .
Is the inspection result normal?
YES- GO TO 6.
NO- Replace malfunctioning fuel injector. Refer to "Exploded View" Exploded View.
6. CHECK INTERMITTENT INCIDENT
Refer to "Intermittent Incident" Intermittent Incident.
Is the inspection result normal?
YES- Replace IPDM E/R. Refer to "Removal and Installation" Removal and Installation.
NO- Repair open circuit, short to ground or short to power in harness or connectors.
Component Inspection
1. CHECK FUEL INJECTOR
1.Turn ignition switch OFF.
2.Disconnect fuel injector harness connector.
3.Check resistance between fuel injector terminals as follows.
Is the inspection result normal?
YES- INSPECTION END
NO- Replace malfunctioning fuel injector. Refer to "Removal and Installation" Removal and Installation.