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 | |
| Starter signal circuit | ||
| Entry and start system (w/ entry and start system) | ||
| VC output circuit (ECM 5 V output) | ||
| No initial combustion (Does not start) | Engine immobiliser system (w/ entry and start system) | |
| Engine immobiliser system (w/o entry and start system) | ||
| ECM power source circuit | ||
| VC output circuit (ECM 5 V output) | ||
| Crankshaft position sensor | ||
| Fuel pump control circuit | ||
| Ignition system | ||
| Fuel injector circuit | ||
| Valve timing | ||
| No. 1 valve rocker arm sub-assembly* | ||
| Engine cranks normally but difficult to start | Fuel pump control circuit | |
| Fuel pump | ||
| Engine coolant temperature sensor | ||
| Ignition system | ||
| Fuel injector assembly | ||
| Compression | ||
| Fuel injector circuit | ||
| ECM power source circuit | ||
| Intake system | ||
| Throttle body assembly | ||
| No. 1 valve rocker arm sub-assembly* | ||
| Incomplete intermittent combustion occurs (Does not start) | Fuel pump control circuit | |
| Fuel pump | ||
| Fuel line | - | |
| Ignition system | ||
| Fuel injector assembly | ||
| Crankshaft position sensor | ||
| Valve timing | ||
| High engine speed (Poor idle) | Air conditioning signal circuit | |
| Throttle body assembly | ||
| Intake system | ||
| Engine coolant temperature sensor | ||
| ECM power source circuit | ||
| PCV hose | ||
| PCV valve | ||
| Low engine speed (Poor idle) | Fuel pump control circuit | |
| Throttle body assembly | ||
| Intake system | ||
| PCV hose | ||
| PCV valve | ||
| Engine stalls on deceleration | Idle speed (refer to "Low engine speed" symptom) | - |
| Rough idle | Compression | |
| Air fuel ratio sensor | ||
| Heated oxygen sensor | ||
| Mass air flow meter sub-assembly | ||
| Ignition system | ||
| Fuel line | - | |
| Fuel pump | ||
| Intake system | ||
| PCV hose | ||
| PCV valve | ||
| No. 1 valve rocker arm sub-assembly* | ||
| External part malfunction (Increase in load: A/C system, CVT system, etc.) | - | |
| Hunting (Poor idle) | PCV hose | |
| PCV valve | ||
| Mass air flow meter sub-assembly | ||
| Air fuel ratio sensor | ||
| Engine stalls during air conditioning operation | Air conditioning signal circuit | |
| ECM | ||
| Hesitation/Poor acceleration (Poor driveability) | Fuel line | - |
| Fuel pump | ||
| Valve timing | ||
| Mass air flow meter sub-assembly | ||
| Throttle body assembly | ||
| Knock control sensor | ||
| Fuel injector assembly | ||
| Ignition system | ||
| Compression | ||
| Brake override system | ||
| No. 1 valve rocker arm sub-assembly* | ||
| Surging (Poor driveability) | Fuel line | - |
| Fuel pump control circuit | ||
| Fuel pump | ||
| Ignition system | ||
| Fuel injector assembly | ||
| No. 1 valve rocker arm sub-assembly* | ||
| Engine stalls soon after starting | Mass air flow meter sub-assembly | |
| Intake system | ||
| Fuel line | - | |
| Valve timing | ||
| No. 1 valve rocker arm sub-assembly* |
Tech Tips
*: Check "Fuel Cut Elps Time" in the Data List. If the elapsed time is over 0 sec, then the engine speed is high (More than the engine speed at which fuel cut occurs + 500 rpm). When this has happened, there is a possibility that the No. 1 valve rocker arm sub-assembly will become loose and malfunction, so check that the No. 1 valve rocker arm sub-assembly is properly attached.