2NZ-FE ENGINE CONTROL SFI SYSTEM PROBLEM SYMPTOMS TABLE
- HINT:
- ·
Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table. Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.
·Inspect the fuses and relays related to this system before inspecting the suspected areas below.
| Symptom | Suspected Area | Link |
|---|---|---|
| Engine does not crank (Does not start) | Battery | 
|
| Starter signal circuit |
|
|
| Park/neutral position switch |
|
|
| VC output circuit (ECM 5 V output) |
|
|
| No initial combustion (Does not start) | Engine immobiliser system |
|
| ECM power source circuit |
|
|
| VC output circuit (ECM 5 V output) |
|
|
| Crankshaft position sensor |
|
|
| Ignition system |
|
|
| Fuel pump control circuit |
|
|
| Ignition system |
|
|
| Fuel injector circuit |
|
|
| Camshaft position sensor |
|
|
| Valve timing |
|
|
| ECM |
|
|
| Engine cranks normally but difficult to start | Fuel pump control circuit |
|
| Fuel pump |
|
|
| Fuel injector assembly |
|
|
| ECM power source circuit |
|
|
| Starter signal circuit |
|
|
| Engine coolant temperature sensor |
|
|
| Ignition system |
|
|
| Intake system |
|
|
| Spark plug |
|
|
| Throttle body with motor assembly |
|
|
| Compression |
|
|
| Crankshaft position sensor |
|
|
| Incomplete intermittent combustion occurs (Does not start) | Fuel pump control circuit |
|
| Fuel pump |
|
|
| Fuel line | - | |
| Ignition system |
|
|
| Intake system |
|
|
| Fuel injector circuit |
|
|
| Fuel injector assembly |
|
|
| ECM power source circuit |
|
|
| Starter signal circuit |
|
|
| Crankshaft position sensor |
|
|
| Camshaft position sensor |
|
|
| Valve timing |
|
|
| High engine speed | Throttle body with motor assembly |
|
| Intake system |
|
|
| Air conditioning signal circuit |
|
|
| ECM power source circuit |
|
|
| Engine coolant temperature sensor |
|
|
| PCV valve and hose |
|
|
| Low engine speed (Poor idle) | Throttle body with motor assembly |
|
| Air conditioning signal circuit |
|
|
| Fuel pump control circuit |
|
|
| Fuel pump |
|
|
| Intake system |
|
|
| PCV valve and hose |
|
|
| Rough idle | Compression |
|
| Spark plug |
|
|
| Fuel injector circuit |
|
|
| ECM power source circuit |
|
|
| Fuel injector assembly |
|
|
| Fuel pump control circuit |
|
|
| Fuel pump |
|
|
| Fuel line | - | |
| Throttle body with motor assembly |
|
|
| Ignition system |
|
|
| Intake system |
|
|
| Purge VSV |
|
|
| PCV valve and hose |
|
|
| Heated oxygen sensor |
|
|
| Mass air flow meter sub-assembly |
|
|
| Knock control sensor |
|
|
| External part malfunction (Increase in load: A/C system, etc.) | - | |
| Hunting (Poor idle) | Throttle body with motor assembly |
|
| Intake system |
|
|
| PCV valve and hose |
|
|
| Mass air flow meter sub-assembly |
|
|
| Hesitation and/or poor acceleration (Poor driveability) | Fuel pump control circuit |
|
| Fuel pump |
|
|
| Fuel line | - | |
| Fuel injector assembly |
|
|
| Spark plug |
|
|
| Ignition system |
|
|
| Fuel injector circuit |
|
|
| ECM power source circuit |
|
|
| Mass air flow meter sub-assembly |
|
|
| Throttle body with motor assembly |
|
|
| Intake system |
|
|
| Knock control sensor |
|
|
| Valve timing |
|
|
| Compression |
|
|
| Brake override system |
|
|
| Surging (Poor driveability) | Spark plug |
|
| Fuel pump control circuit |
|
|
| Fuel pump |
|
|
| Fuel injector assembly |
|
|
| Ignition system |
|
|
| Fuel injector circuit |
|
|
| ECM power source circuit |
|
|
| Mass air flow meter sub-assembly |
|
|
| Variable Valve Timing (VVT) system |
|
|
| Compression |
|
|
| Engine stalls soon after starting | Fuel pump control circuit |
|
| Fuel pump |
|
|
| Fuel injector assembly |
|
|
| Spark plug |
|
|
| Ignition system |
|
|
| Fuel injector circuit |
|
|
| ECM power source circuit |
|
|
| Mass air flow meter sub-assembly |
|
|
| Variable Valve Timing (VVT) system |
|
|
| Throttle body with motor assembly |
|
|
| Intake system |
|
|
| PCV valve and hose |
|
|
| Compression |
|
|
| Engine stalls only during A/C operation | Air conditioning signal circuit |
|
| ECM |
|