The injectors inject fuel according to a signal coming from the PCM. The amount of fuel injected by the injectors is determined by the time during which the solenoid valve is energized. The amount of time the solenoid valve is energized is determined by the pulse width of the signal from the PCM.
Check Item | Data display | Check conditions | Check content | Test specification |
Injector | Drive time (at staring) | Engine: Cranking | 0°C (32°F) | Approx. 17 ms |
20°C (68°F) | Approx. 35 ms | |||
80°C (176°F) | Approx. 8.5 ms |
Drive time indicates the injector activation time when the supply voltage is 11V and the cranking speed is less than 250 rpm.
Check Item | Data display | Check conditions | Engine state | Test specification |
Injector | Drive time | ● Engine coolant temperature: 80 to 95°C (176 to 205°F) ● Lamps, electric cooling fan, accessory modules: All OFF ● Transaxle: Neutral (P range for vehicle with A/T) ● Steering wheel: Neutral | Idle rpm | 2.2~2.9 ms |
2,000 rpm | 1.8~2.6 ms | |||
Rapid racing | Increasing |
When engine coolant temperature is lower than 0°C (32°F), the PCM fires all four cylinders simultaneously.
When the vehicle is new (within initial operation of about 500 km [300 miles]), the injector drive time may be about 10% longer.
Check Item | Item No. | Drive content | Check condition | Normal state |
Injector ● Actuator test | 01 | No. 1 injector shut off | Engine: Idling after warm-up (Shut off the injectors in sequence during and after engine warm-up; checkthe idle condition) | Idle should become unstable as injector shuts off. |
02 | No. 2 injector shut off | |||
03 | No. 3 injector shut off | |||
04 | No. 4 injector shut off | |||
05 | No. 5 injector shut off | |||
06 | No. 6 injector shut off |
Using a stethoscope, check the injectors for a clicking sound at idle. Check that the sound is produced at shorter intervals as the enginespeed increases.
Ensure that the sound from an adjacent injector is not being transmitted along the delivery pipe to an inoperative injector.
If a stethoscope is not available, check the injector operation with your finger. If no vibration is felt, check the wiring connector, injectoror injection signal from the PCM.
Disconnect the connector at the injector.
Measure the resistance between terminals.
Standard value : 13~16Ω [at 20°C (68°F)] |
Re-connect the connector to the injector.
If the engine is hard to start when hot, check for fuel pressure and injector leaks.
If the injectors do not operate when the engine is cranked, then check the followings:
● Defective power supply circuit to the PCM, faulty ground circuit ● Defective control relay ● Defective crankshaft position (CKP) sensor or camshaft position (CMP) sensor |
If there is any cylinder whose idle state remains unchanged when the fuel injectors are cut one after another during idling, check for thefollowing items about that a cylinder.
● Injector and harness ● Ignition plug and high tension cable ● Compression pressure |
If the injection system is OK but the injector drive time is out of specification, check for the following items.
● Poor combustion in the cylinder (faulty ignition plug, ignition coil, compression pressure, etc.) ● Loose EGR valve seating |
