SFI SYSTEM PROBLEM SYMPTOMS TABLE
Tech Tips
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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.
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Inspect the fuses and relays related to this system before inspecting the suspected areas below.
| Symptom | Suspected Area | See page |
|---|---|---|
| Engine does not crank (Does not start) | Battery | |
| Starter relay | ||
| Starter assembly | ||
| VC output circuit (ECM 5 V output) | ||
| Starter signal circuit | ||
| Smart access system with push-button start (for start function) | ||
| Park/neutral position switch assembly (for AA81E) | ||
| Park/neutral position switch assembly (for A760H) | ||
| No initial combustion (Does not start) | Engine immobiliser system | |
| ECM power source circuit | ||
| VC output circuit (ECM 5 V output) | ||
| Crankshaft position sensor | ||
| VVT sensor | ||
| Fuel pump control circuit | ||
| Fuel injector circuit | ||
| Ignition system | ||
| Valve timing | ||
| Starter signal circuit | ||
| ECM | ||
| Engine cranks normally but difficult to start | Fuel pump control circuit | |
| Fuel pump (for high pressure) | ||
| Engine coolant temperature sensor | ||
| Ignition system | ||
| Fuel injector assembly (for port injection) | ||
| Fuel injector assembly (for direct injection) | ||
| Compression | ||
| Intake system | ||
| Throttle body with motor assembly | ||
| PCV hose (w/ canister pump module) | ||
| PCV hose (w/o canister pump module) | ||
| Starter signal circuit | ||
| ECM power source circuit | ||
| Incomplete intermittent combustion occurs (Does not start) | Fuel pump control circuit | |
| Ignition system | ||
| Fuel line | ||
| Fuel pump | ||
| Fuel injector assembly (for port injection) | ||
| Fuel injector assembly (for direct injection) | ||
| Crankshaft position sensor | ||
| VVT sensor | ||
| Valve timing | ||
| Starter signal circuit | ||
| ECM power source circuit | ||
| High engine speed (Poor idle) | A/C signal circuit | |
| Throttle body with motor assembly | ||
| Intake system | ||
| Engine coolant temperature sensor | ||
| PCV hose (w/ canister pump module) | ||
| PCV hose (w/o canister pump module) | ||
| PCV system | ||
| ECM power source circuit | ||
| Low engine speed (Poor idle) | Fuel pump control circuit | |
| Fuel pump (for high pressure) | ||
| Throttle body with motor assembly | ||
| Intake system | ||
| PCV hose (w/ canister pump module) | ||
| PCV hose (w/o canister pump module) | ||
| Rough idle | Compression (engine mechanical) | |
| Air fuel ratio sensor | ||
| Heated oxygen sensor | ||
| Mass air flow meter | ||
| Ignition system | ||
| A/C signal circuit | ||
| Fuel injector assembly (for port injection) | ||
| Fuel injector assembly (for direct injection) | ||
| Fuel line | ||
| Fuel pump | ||
| Fuel pump (for high pressure) | ||
| Intake system | ||
| Electronic throttle control system | ||
| PCV hose (w/ canister pump module) | ||
| PCV hose (w/o canister pump module) | ||
| Hunting (Poor idle) | Electronic throttle control system | |
| Intake system | ||
| ECM power source circuit | ||
| PCV hose (w/ canister pump module) | ||
| PCV hose (w/o canister pump module) | ||
| Mass air flow meter | ||
| Air fuel ratio sensor | ||
| Hesitation/Poor acceleration (Poor driveability) | Fuel line | |
| Fuel pump | ||
| Fuel pump (for high pressure) | ||
| Spark plug | ||
| Ignition system | ||
| Fuel injector assembly (for port injection) | ||
| Fuel injector assembly (for direct injection) | ||
| ECM power source circuit | ||
| Mass air flow meter | ||
| Throttle body with motor assembly | ||
| Knock control sensor | ||
| Compression | ||
| Brake override system | ||
| Surging (Poor driveability) | Spark plug | |
| Fuel line | ||
| Fuel pump control circuit | ||
| Fuel pump (for high pressure) | ||
| Ignition system | ||
| Fuel injector assembly (for port injection) | ||
| Fuel injector assembly (for direct injection) | ||
| ECM power source circuit | ||
| Mass air flow meter | ||
| Variable Valve Timing (VVT) system | ||
| Compression | ||
| Engine stalls soon after starting | Fuel pump control circuit | |
| Fuel pump | ||
| Fuel pump (for high pressure) | ||
| Fuel line | ||
| Spark plug | ||
| Ignition system | ||
| Fuel injector assembly (for port injection) | ||
| Fuel injector assembly (for direct injection) | ||
| ECM Power Source Circuit | ||
| Mass air flow meter | ||
| Variable Valve Timing (VVT) system | ||
| Throttle body with motor assembly | ||
| Intake system | ||
| PCV valve and hose | ||
| Compression | ||
| Engine stalls only during A/C operation | A/C signal circuit | |
| ECM | ||
| Unable/difficult to refuel* | Fuel system (canister, refueling valve, roll over valve, fuel tank, etc.) | - |
| SNOW mode does not change | Pattern select switch snow mode circuit |
*: w / Canister Pump Module