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 | See page |
|---|---|---|
| Engine does not crank (Does not start) | Battery | |
| ST relay | ||
| Starter assembly*1 | ||
| Starter assembly*2 | ||
| Starter assembly*3 | ||
| Starter assembly*4 | ||
| Park/neutral position switch*5 | ||
| Clutch start switch assembly*6 | ||
| Entry and start system (for start function)*7 | ||
| Starter signal circuit*8 | ||
| VC output circuit*7 | ||
| Stop and start system*1 | ||
| When being restarted due to stop and start system control, engine does not crank (Does not start)*1 | Stop and start system*1 | |
| No initial combustion (Does not start) | ECM power source circuit | |
| VC output circuit*8 | ||
| Crankshaft position sensor | ||
| Ignition circuit | ||
| Ignition system | ||
| Fuel pump control circuit | ||
| Fuel pump | ||
| Fuel injector circuit | ||
| Fuel injector assembly | ||
| Camshaft position sensor (for intake camshaft) | ||
| Camshaft position sensor (for exhaust camshaft) | ||
| Valve timing | ||
| Cranking holding function circuit*7 | ||
| Starter signal circuit*8 | ||
| Engine immobiliser system (w/ entry and start system)*7 | ||
| Engine immobiliser system (w/o entry and start system)*8 | ||
| No. 1 valve rocker arm sub-assembly*11 | ||
| ECM | ||
| Engine cranks normally but difficult to start | Fuel pump control circuit | |
| Fuel pump | ||
| Fuel injector circuit | ||
| Fuel injector assembly | ||
| ECM power source circuit | ||
| Cranking holding function circuit*7 | ||
| Starter signal circuit*8 | ||
| Engine coolant temperature sensor | ||
| Ignition system | ||
| Ignition circuit | ||
| Intake system | ||
| Spark plug | ||
| Throttle body with motor assembly | ||
| Crankshaft position sensor | ||
| Compression | ||
| EGR valve assembly | ||
| No. 1 valve rocker arm sub-assembly*11 | ||
| Incomplete intermittent combustion occurs (Does not start) | Fuel pump control circuit | |
| Fuel pump | ||
| Fuel line | ||
| Ignition circuit | ||
| Ignition system | ||
| Intake system | ||
| Fuel injector circuit | ||
| Fuel injector assembly | ||
| Spark plug | ||
| ECM power source circuit | ||
| Cranking holding function circuit*7 | ||
| Starter signal circuit*8 | ||
| Crankshaft position sensor | ||
| Camshaft position sensor (for intake camshaft) | ||
| Camshaft position sensor (for exhaust camshaft) | ||
| Valve timing | ||
| High engine speed | Throttle body with motor assembly | |
| Intake system | ||
| Air conditioning signal circuit*9 | ||
| Air conditioning signal circuit*10 | ||
| Engine coolant temperature sensor | ||
| PCV valve and hose | ||
| EGR valve assembly | ||
| Low engine speed (Poor idling) | Throttle body with motor assembly | |
| Air conditioning signal circuit*9 | ||
| Air conditioning signal circuit*10 | ||
| Fuel pump control circuit | ||
| Fuel pump | ||
| Intake system | ||
| PCV valve and hose | ||
| EGR valve assembly | ||
| Rough idle | Compression | |
| Spark plug | ||
| Fuel injector circuit | ||
| ECM power source circuit | ||
| Fuel pump control circuit | ||
| Fuel pump | ||
| Fuel injector assembly | ||
| Fuel line | ||
| Throttle body with motor assembly | ||
| Ignition circuit | ||
| Ignition system | ||
| Intake system | ||
| Purge VSV | ||
| PCV valve and hose | ||
| Air fuel ratio sensor | ||
| Heated oxygen sensor | ||
| Mass air flow meter | ||
| Knock sensor | ||
| EGR valve assembly | ||
| No. 1 valve rocker arm sub-assembly*11 | ||
| External part malfunction (Increase in load: A/C system, CVT system, etc.) | - | |
| Hunting (Poor idling) | Throttle body with motor assembly | |
| Intake system | ||
| PCV valve and hose | ||
| Mass air flow meter | ||
| Air fuel ratio sensor | ||
| EGR valve assembly | ||
| Hesitation/Poor acceleration (poor drivability) | Fuel pump control circuit | |
| Fuel line | ||
| Fuel pump | ||
| Fuel injector assembly | ||
| Spark plug | ||
| Ignition system | ||
| Ignition circuit | ||
| Fuel injector circuit | ||
| ECM power source circuit | ||
| Mass air flow meter | ||
| Throttle body with motor assembly | ||
| Knock sensor | ||
| Intake system | ||
| Valve timing | ||
| Compression | ||
| EGR valve assembly | ||
| No. 1 valve rocker arm sub-assembly*11 | ||
| Brake override system | ||
| Surging (Poor drivability) | Spark plug | |
| Fuel pump control circuit | ||
| Fuel pump | ||
| Fuel injector assembly | ||
| Ignition system | ||
| Ignition circuit | ||
| Fuel injector circuit | ||
| ECM power source circuit | ||
| Mass air flow meter | ||
| Variable Valve Timing (VVT) system | ||
| Compression | ||
| No. 1 valve rocker arm sub-assembly*11 | ||
| Engine stalls soon after starting | Fuel pump control circuit | |
| Fuel pump | ||
| Fuel injector assembly | ||
| Spark plug | ||
| Ignition system | ||
| Ignition circuit | ||
| Fuel injector circuit | ||
| 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 | ||
| No. 1 valve rocker arm sub-assembly*11 | ||
| Engine stalls during air conditioning operation | Air conditioning signal circuit*9 | |
| Air conditioning signal circuit*10 | ||
| ECM |
*1: except Cold Area Specification Vehicles
*2: for cold Area Specification Vehicles
*3: for Transaxle CVT with Stop and Start System
*4: for Transaxle MT with Stop and Start System
*5: for CVT
*6: for Manual Transaxle
*7: w/ Entry and Start System
*8: w/o Entry and Start System
*9: for Automatic Air Conditioning System
*10: for Manual Air Conditioning System
Tech Tips
*11: Check the "Fuel Cut Elps Time" value in the Data List. If the value is more than 0 seconds, a high engine speed (fuel cut speed + 500 rpm or more) has occurred in the past. Since the problem may be caused by valve rocker arm detaching due to an extremely high engine speed, check that the valve rocker arms are properly attached Click here.