1. The engine starts with difficulty or does not start.
2. The engine runs erratically at idle.
3. The engine is unstable in all modes.
If any of the aforementioned situations occur, perform routine diagnostics first (ignition system, engine adjustment, etc.), then check the components of the MFI system with the HI-SCAN scanner.
Note.
- Before removing or replacing any element of the system, read the trouble codes, then disconnect the wire from the negative terminal of the battery.
- Before disconnecting the wire from the negative terminal of the battery, turn off the ignition. Disconnecting the wire while the engine is running or the ignition is on can damage the ECM.
- The oxygen sensor connection to the ECM is shielded wire to reduce possible radio interference from the ignition system. If the shielding braid is damaged, the wire must be replaced.
- When checking the alternator, do not disconnect the wire from the positive battery terminal to prevent damage to the ECM.
- When charging the battery installed in the vehicle from an external source, to prevent damage to the ECM, first disconnect the wires of the vehicle's on-board network from the battery terminals.