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Home >> Lexus >> 2012 >> RX 450h 3.5L Eng VIN C >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (Diagnostics - Introduction) >> SFI System >> Problem Symptoms Table >> Problem Symptoms Table
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Problem Symptoms Table

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SFI SYSTEM

Symptom Suspected Area See
Engine does not crank (Does not start) Hybrid control system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
VC output circuit Refer to VC Output Circuit
No initial combustion (Does not start) ECM power source circuit Refer to ECM Power Source Circuit
VC output circuit Refer to VC Output Circuit
Crankshaft position sensor Refer to INSPECTION
Fuel pump control circuit Refer to Fuel Pump Control Circuit
Ignition system Refer to ON-VEHICLE INSPECTION
Fuel injector circuit Refer to Fuel Injector Circuit
Valve timing Refer to PROCEDURE - Step 4
Engine cranks normally but difficult to start Fuel pump control circuit Refer to Fuel Pump Control Circuit
Fuel pump Refer to INSPECTION
Engine coolant temperature sensor Refer to INSPECTION
Ignition system Refer to ON-VEHICLE INSPECTION
Fuel injector assembly Refer to INSPECTION
EGR valve assembly Refer to INSPECTION
Compression Refer to ON-VEHICLE INSPECTION - Step 10
Fuel injector circuit Refer to Fuel Injector Circuit
Intake system Refer to ON-VEHICLE INSPECTION
Throttle with motor body assembly Refer to ON-VEHICLE INSPECTION
ECM power source circuit Refer to ECM Power Source Circuit
Incomplete intermittent combustion occurs (Does not start) Fuel pump control circuit Refer to Fuel Pump Control Circuit
Fuel pump Refer to INSPECTION
Fuel line -
Ignition system Refer to ON-VEHICLE INSPECTION
Fuel injector assembly Refer to INSPECTION
EGR valve assembly Refer to INSPECTION
Crankshaft position sensor Refer to INSPECTION
Valve timing Refer to PROCEDURE - Step 4
High engine speed (Poor idle) Throttle with motor body assembly Refer to ON-VEHICLE INSPECTION
Throttle with motor body assembly control -
Intake system Refer to ON-VEHICLE INSPECTION
Engine coolant temperature sensor Refer to INSPECTION
PCV hose Refer to ON-VEHICLE INSPECTION - Step 2
PCV system Refer to ON-VEHICLE INSPECTION
ECM power source circuit Refer to ECM Power Source Circuit
Low engine speed (Poor idle) Fuel pump control circuit Refer to Fuel Pump Control Circuit
Throttle with motor body assembly Refer to ON-VEHICLE INSPECTION
Throttle with motor body assembly control -
Intake system Refer to ON-VEHICLE INSPECTION
PCV hose Refer to ON-VEHICLE INSPECTION - Step 2
PCV system Refer to ON-VEHICLE INSPECTION
Engine stalls on deceleration Idle speed (refer to "Low engine speed") Refer to ON-VEHICLE INSPECTION - Step 9
EGR valve assembly Refer to INSPECTION
Rough idle Compression (engine mechanical) Refer to ON-VEHICLE INSPECTION - Step 10
Air fuel ratio sensor Refer to INSPECTION
Heated oxygen sensor Refer to INSPECTION
Mass air flow meter sub-assembly Refer to ON-VEHICLE INSPECTION
Ignition system Refer to ON-VEHICLE INSPECTION
Fuel line -
Valve timing Refer to PROCEDURE - Step 4
Fuel pump Refer to INSPECTION
Intake system Refer to ON-VEHICLE INSPECTION
PCV hose Refer to ON-VEHICLE INSPECTION - Step 2
PCV system Refer to ON-VEHICLE INSPECTION
EGR valve assembly Refer to INSPECTION
Hunting (Poor idle) PCV hose Refer to ON-VEHICLE INSPECTION - Step 2
PCV system Refer to ON-VEHICLE INSPECTION
Mass air flow meter sub-assembly Refer to ON-VEHICLE INSPECTION
Air fuel ratio sensor Refer to INSPECTION
Hesitation/Poor acceleration (Poor driveability) Fuel line -
Fuel pump Refer to INSPECTION
Valve timing Refer to PROCEDURE - Step 4
Mass air flow meter sub-assembly Refer to ON-VEHICLE INSPECTION
Throttle with motor body assembly Refer to ON-VEHICLE INSPECTION
Knock control sensor Refer to INSPECTION
Surging (Poor driveability) Fuel line -
Fuel pump control circuit Refer to Fuel Pump Control Circuit
Fuel pump Refer to INSPECTION
Ignition system Refer to ON-VEHICLE INSPECTION
Fuel injector assembly Refer to INSPECTION
Engine stalls soon after starting Mass air flow meter sub-assembly Refer to ON-VEHICLE INSPECTION
Intake system Refer to ON-VEHICLE INSPECTION
Fuel line -
EGR valve assembly Refer to INSPECTION
Unable/difficult to refuel Fuel system (canister, refueling valve, roll over valve, fuel tank, etc.) -