Engine Control System: Troubleshooting: Notes

First check the basic units when servicing the engine. Check the basic units as below when the engine does not crank, make rough idling or make inferior accelerating.

1. Power supply
   1. Battery
   2. Fusible link
   3. Fuse
2. Body ground
3. Fuel supply
   1. Fuel line
   2. Fuel filter
   3. Fuel pump
4. Ignition system
   1. Spark plug
   2. High tension cable
   3. Ignition coil
5. Emission control system
   1. PCV system
   2. Vacuum leak
6. Others
   1. Ignition timing
   2. Idle speed

Trouble with MFI system is often caused by poor contact of the harness connectors. It is important to check all harness connectors and verify that they are securely connected.