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) | Hybrid control system | |
| VC output circuit | ||
| No initial combustion (does not start) | ECM power source circuit | |
| VC output circuit | ||
| Crankshaft position sensor | ||
| Fuel pump control circuit | ||
| Fuel pump (for low pressure) | ||
| Ignition system | ||
| Fuel injector assembly (for direct injection) | ||
| Fuel injector assembly (for port injection) | ||
| Valve timing | ||
| Engine cranks normally but difficult to start | Fuel pump control circuit | |
| Fuel pump (for high pressure) | ||
| Fuel pump (for low pressure) | ||
| Engine coolant temperature sensor | ||
| Ignition system | ||
| Fuel injector assembly (for direct injection) | ||
| Fuel injector assembly (for port injection) | ||
| Compression | ||
| ECM power source circuit | ||
| Intake system | ||
| Throttle body with motor assembly | ||
| PCV valve and hose | ||
| Crankshaft position sensor | ||
| EGR valve assembly | ||
| Incomplete intermittent combustion occurs (does not start) | Fuel pump control circuit | |
| Fuel line | - | |
| Ignition system | ||
| Fuel injector assembly (for direct injection) | ||
| Fuel injector assembly (for port injection) | ||
| EGR valve assembly | ||
| ECM power source circuit | ||
| Crankshaft position sensor | ||
| Valve timing | ||
| High engine speed | Throttle body with motor assembly | |
| Intake system | ||
| ECM power source circuit | ||
| Engine coolant temperature sensor | ||
| PCV system | ||
| Low engine speed (poor idle) | Throttle body with motor assembly | |
| Fuel pump control circuit | ||
| Fuel pump (for low pressure) | ||
| Fuel pump (for high pressure) | ||
| Intake system | ||
| PCV system | ||
| Rough idle | Compression | |
| Throttle body with motor assembly | ||
| Ignition system | ||
| Air fuel ratio sensor | ||
| Heated oxygen sensor | ||
| Mass air flow meter sub-assembly | ||
| Manifold absolute pressure sensor | ||
| Fuel line | - | |
| Valve timing | ||
| Intake system | ||
| PCV system | ||
| Fuel pump control circuit | - | |
| Fuel injector assembly (for direct injection) | ||
| Fuel injector assembly (for port injection) | ||
| EGR valve assembly | ||
| Hunting (poor idle) | PCV system | |
| Air fuel ratio sensor | ||
| Mass air flow meter sub-assembly | ||
| ECM power source circuit | ||
| Fuel pump control circuit | ||
| Throttle body with motor assembly | ||
| Air fuel ratio sensor | ||
| Ignition system | ||
| Drive start control system | ||
| Hesitation and/or poor acceleration | Fuel line | - |
| Fuel pump control circuit | ||
| Fuel pump (for low pressure) | ||
| Fuel pump (for high pressure) | ||
| Ignition system | ||
| Valve timing | ||
| Mass air flow meter sub-assembly | ||
| Throttle body with motor assembly | ||
| Knock control sensor | ||
| Brake override system | ||
| Drive start control system | ||
| Surging (poor driveability) | Fuel line | - |
| Fuel pump control circuit | ||
| Fuel pump (for low pressure) | ||
| Fuel pump (for high pressure) | ||
| Ignition system | ||
| Fuel injector assembly (for direct injection) | ||
| Fuel injector assembly (for port injection) | ||
| Engine stalls soon after starting | Mass air flow meter sub-assembly | |
| Manifold absolute pressure sensor | ||
| Fuel line | - | |
| Fuel pump control circuit | ||
| Throttle body with motor assembly | ||
| Ignition system | ||
| Crankshaft position sensor | ||
| Valve timing | ||
| EGR valve assembly |