Circuit Inspection

FUEL INJECTOR

The injectors injector fuel according to a signal coming from the ECM. The amount of fuel injected by the injectors is determined by the time which the solenoid valve is energized.

Circuit Diagram:

Troubleshooting Hints

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

2. If the injector does not operate when the engine is cranked, then check the followings;
- Faulty power supply circuit to the ECM, faulty ground circuit
- Faulty control relay
- Faulty crankshaft position (CKP) sensor, camshaft position (CMP) sensor

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

4. 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

Harness Inspection Procedures: