Component Test

ON-VEHICLE INSPECTION:

1. With the engine running, use a mechanic's stethoscope to listen to each injector.

Checking Fuel Injector Operation By Sound:

2. Each injector should make a sharp "clicking" sound that increases with the speed of the engine.
3. If a stethoscope is not available, check the injectors by touching each injector with your finger and feeling for solenoid operation.

Checking Fuel Injector Operation By Touch:

4. If no sound or transmission is felt, check the wiring, connector, injector spray test or injection signal from the ECU. (Refer to INJECTOR CIRCUIT TEST)
5. Turn engine off.
6. Carefully disconnect wire connector to any suspected injector.
7. Using an Ohmmeter, measure the resistance across the injector terminals.

Measuring Fuel Injector Resistance:

Resistance: Approx. 13.8 Ohms

8. If not as specified, replace the Fuel Injector.
9. Reconnect the injector connector, ensuring that the connector spring clips securely.

INJECTOR SPRAY TEST:

1. Remove injectors per COMPONENT REPLACEMENT AND REPAIR PROCEDURES.
2. Utilizing special service tools (SST), connect the injector to the fuel filter and the Fuel Pressure Regulator.

Testing Fuel Injector Operation With Special Service Tools (SST):

3. Attach the Fuel Pressure Regulator to the vehicle fuel return line with SST.

Connecting FPR To Special Service Tools (SST):

4. Using SST clamp, attach the injector to the fuel hose.

Connecting Fuel Injector To Special Service Tools (SST):

5. Place the tip of the injector in a graduated beaker. Turn on the ignition switch.
6. Using a service wire, short terminals +B and FP on the engine check connector.

Shorting Fuel Pump Test Terminals:

7. Connect a SST jumper wire to the injector terminals and apply battery current to the injector for 15 seconds.

Testing Fuel Injector Operation - Current Applied:

8. Measure the injection volume of each injector. Repeat test 2 or 3 times on each injector to ensure accuracy.

Volume: 40 - 50cc (2.4 - 3.1 cu in.) per 15 sec.

9. If not within specifications, replace the Fuel Injector.
10. Test all injectors for volume variance. There should be 5cc (0.3 cu in.) or less difference.
11. After testing injection volume, remove current from injector and test for leakage.
12. If the injector leaks more than one drop per minute, replace the injector.
13. Remove the service wire from the engine check connector and turn off the ignition switch.
14. Remove the SST from the injectors and Fuel Pressure Regulator.
15. Install Fuel Injectors and components as prescribed in COMPONENT REPLACEMENT AND REPAIR PROCEDURES.