Troubleshooting Hints
TROUBLESHOOTING HINTS1. Engine trouble are usually not caused by the Electronic Fuel Injection (EFI) system. When troubleshooting, always first check the condition of the other systems.
a. Electronic sources.
- Battery.
- Fusible links.
- Fuses.
b. Body ground.
c. Fuel supply.
- Fuel leakage.
- Fuel filter.
- Fuel pump.
d. Ignition system.
- Spark plugs.
- High-tension cords.
- Distributor.
- Ignition coil.
- Igniter.
e. Air induction system.
- Vacuum leaks.
f. Emission control system.
- Positive Crankcase Ventilation (PCV) system.
- Exhaust Gas Recirculation (EGR) system.
g. Others.
- Ignition timing.
- Idle speed.
- etc..
2. The most frequent cause of problems is simply a bad contact in wiring connectors. Always check that connections are secure.
When inspecting the connector, pay particular attention to the following points:
a. Check to see that the terminals are not bent.
b. Check to see that the connector is pushed in completely and locked.
c. Check to see that there is no signal change when the connector is slightly tapped or wiggled.
3. Sufficiently troubleshooting for other causes before replacing the Electronic Control Unit (ECU), as the ECU is of high quality and expensive.
4. Use a volt/ohmmeter with high impedance (10 k-ohms/V minimum) for troubleshooting of the electrical circuit.