Fuel Injector: Testing and Inspection

Injectors:

Fuel Injector:

TROUBLESHOOTING HINTS

Hint 1: If the engine is hard to start when hot, check fuel pressure and check the injector for leaks.

Hint 2: If the injector does not when the engine that is hard to start is cranked, check the following;
- Faulty power supply circuit to the engine control module, faulty ground circuit.
- Faulty multi port fuel injection relay.
- Faulty crankshaft position sensor, camshaft position sensor.

Hint 3: If there is any cylinder whose idle state remains unchanged when the fuel injection of injectors is cut one after another during idling, make following checks about such cylinder.
- Injector and harness check
- Spark plug and high tension cable check
- Compression pressure check

Hint 4: If the injector harness and individual part checks have resulted normal but the injector drive time is out of specification, the following troubles are suspected.
- Poor combustion in the cylinder (faulty spark plug, ignition coil, compression pressure, etc.)
- Loose EGR valve seating
- High engine resistance

HARNESS INSPECTION

Fuel Injector:

ACTUATOR INSPECTION

Fuel Injector:

CHECKING OPERATION SOUND

Using a stethoscope, listen for an operation sound ("chi-chi-chi") of injectors during idling or during cranking.

Check that as the rotating speed increases, the frequency of the operating sound also increases.

NOTE: that even if the injector you are checking is not operating, you will hear the operating sound of the other injectors.

NOTE: If no operating sound is heard from the injector that is being checked, check the injector drive circuit. If there is nothing wrong with the circuit, a defective injector or engine control module is suspected.

Fuel Injector:

RESISTANCE BETWEEN TERMINALS
1. Remove the injector connector.
2. Measure the resistance between terminals.

Standard value: 13 - 16 ohms [at 2O°C (68°F)]

3. Install the injector connector.

SCANTOOL TESTING