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Home >> Lexus >> 2012 >> RX 350 FWD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control (SFI) 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) Battery Refer to ON-VEHICLE INSPECTION - Step 1
Starter signal circuit Refer to Starter Signal Circuit
Smart access system with push button start Refer to HOW TO PROCEED WITH TROUBLESHOOTING
VC output circuit (ECM 5 V output) Refer to VC Output Circuit
Starter assembly Refer to INSPECTION
No initial combustion (Does not start) Immobilizer system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
ECM power source circuit Refer to ECM Power Source Circuit
VC output circuit (ECM 5 V output) 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
Compression Refer to ON-VEHICLE INSPECTION - Step 11
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
Crankshaft position sensor Refer to INSPECTION
Valve timing Refer to PROCEDURE - Step 4
High engine speed (Poor idle) Air conditioning signal circuit Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Throttle with motor body assembly Refer to ON-VEHICLE INSPECTION
Throttle with motor body assembly control -
Engine coolant temperature sensor Refer to INSPECTION
PCV hose Refer to ON-VEHICLE INSPECTION
PCV system Refer to ON-VEHICLE INSPECTION
ACIS control circuit Refer to ACIS Control 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
ACIS control circuit Refer to ACIS Control Circuit
PCV hose Refer to ON-VEHICLE INSPECTION
PCV system Refer to ON-VEHICLE INSPECTION
Engine stalls on deceleration Idle speed (refer to "Low engine speed") Refer to ON-VEHICLE INSPECTION - Step 10
Rough idle Compression (engine mechanical) Refer to ON-VEHICLE INSPECTION - Step 11
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
Air conditioning signal circuit Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Fuel line -
Valve timing Refer to PROCEDURE - Step 4
Fuel pump Refer to INSPECTION
Intake system Refer to ON-VEHICLE INSPECTION
ACIS control circuit Refer to ACIS Control Circuit
PCV hose Refer to ON-VEHICLE INSPECTION
PCV system Refer to ON-VEHICLE INSPECTION
Hunting (Poor idle) PCV hose Refer to ON-VEHICLE INSPECTION
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
ACIS control circuit Refer to ACIS Control Circuit
Engine stalls during air conditioning operation Air conditioning signal circuit (compressor circuit) Refer to HOW TO PROCEED WITH TROUBLESHOOTING
ECM Refer to REMOVAL
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
Air intake control circuit Refer to Air Intake Control Circuit
Brake override system Refer to Brake Override System
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 -
Unable/difficult to refuel Fuel system (canister, refueling valve, roll over valve, fuel tank, etc.) -
Engine vibrates frequently when idling (Active control engine mount system) Active control engine mount circuit Refer to Active Control Engine Mount System