Tech Tips
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 | |
| ST relay | ||
| Starter assembly | ||
| VC output circuit (ECM 5 V output) | ||
| Starter signal circuit | ||
| Entry and start system (for start function) | ||
| Park/neutral position switch assembly | ||
| No initial combustion (Does not start) | Immobiliser system | |
| ECM power source circuit | ||
| VC output circuit (ECM 5 V output) | ||
| Crankshaft position sensor | ||
| VVT sensor (for intake camshaft) | ||
| VVT sensor (for exhaust camshaft) | ||
| Fuel pump control 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 side) | ||
| 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 | ||
| Starter signal circuit | ||
| ECM power source circuit | ||
| Incomplete intermittent combustion occurs (Does not start) | Fuel pump control circuit | |
| Ignition system | ||
| Fuel line | - | |
| Fuel pump (for low pressure side) | ||
| Fuel pump (for high pressure side) | ||
| Fuel injector assembly (for port injection) | ||
| Fuel injector assembly (for direct injection) | ||
| Crankshaft position sensor | ||
| VVT sensor (for intake camshaft) | ||
| VVT sensor (for exhaust camshaft) | ||
| Valve timing | ||
| Starter signal circuit | ||
| ECM power source circuit | ||
| High engine speed | Air conditioning signal circuit | |
| Throttle body with motor assembly | ||
| Intake system | ||
| Engine coolant temperature sensor | ||
| PCV hose | ||
| PCV system | ||
| ECM power source circuit | ||
| Low engine speed (Poor idle) | Fuel pump control circuit | |
| Fuel pump (for high pressure side) | ||
| Throttle body with motor assembly | ||
| Intake system | ||
| PCV hose | ||
| Rough idle | Compression (engine mechanical) | |
| Air fuel ratio sensor | ||
| Heated oxygen sensor | ||
| Mass air flow meter sub-assembly | ||
| Ignition system | ||
| Air conditioning signal circuit | ||
| Fuel injector assembly (for port injection) | ||
| Fuel injector assembly (for direct injection) | ||
| Fuel line | - | |
| Fuel pump (for low pressure side) | ||
| Fuel pump (for high pressure side) | ||
| Intake system | ||
| Electronic throttle control system | ||
| PCV hose | ||
| Hunting (Poor idle) | Electronic throttle control system | |
| Intake system | ||
| ECM power source circuit | ||
| PCV hose | ||
| Mass air flow meter sub-assembly | ||
| Air fuel ratio sensor | ||
| Hesitation/Poor acceleration (Poor driveability) | Fuel line | - |
| Fuel pump (for low pressure side) | ||
| Fuel pump (for high pressure side) | ||
| Spark plug | ||
| Ignition system | ||
| Fuel injector assembly (for port injection) | ||
| Fuel injector assembly (for direct injection) | ||
| ECM power source circuit | ||
| Mass air flow meter sub-assembly | ||
| Throttle body with motor assembly | ||
| Knock control sensor | ||
| Compression (engine mechanical) | ||
| Brake override system | ||
| Surging (Poor driveability) | Spark plug | |
| Fuel line | - | |
| Fuel pump control circuit | ||
| Fuel pump (for high pressure side) | ||
| Ignition system | ||
| Fuel injector assembly (for port injection) | ||
| Fuel injector assembly (for direct injection) | ||
| ECM power source circuit | ||
| Mass air flow meter sub-assembly | ||
| Variable Valve Timing (VVT) system | ||
| Compression (engine mechanical) | ||
| Engine stalls soon after starting | Fuel pump control circuit | |
| Fuel pump (for low pressure side) | ||
| Fuel pump (for high pressure side) | ||
| 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 sub-assembly | ||
| Throttle body with motor assembly | ||
| Intake system | ||
| PCV valve and hose | ||
| Compression (engine mechanical) | ||
| Engine stalls only during A/C operation | Air conditioning signal circuit | |
| ECM | ||
| Unable/difficult to refuel | Fuel system (canister, refueling valve, roll over valve, fuel tank, etc.) | - |
| Drive mode does not change | Drive mode select switch circuit | |
| SNOW mode does not change | Pattern select switch snow mode circuit |