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Home >> Lexus >> 2012 >> IS F >> Repair and Diagnosis >> 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 Refer To
Engine does not crank (Does not start) Battery Refer to ON-VEHICLE INSPECTION
Smart access system with push-button start Refer to HOW TO PROCEED WITH TROUBLESHOOTING
ECM power source circuit Refer to ECM Power Source Circuit
VC output circuit Refer to VC Output Circuit
Cranking holding function circuit Refer to Cranking Holding Function Circuit
Starter Refer to INSPECTION
No initial combustion (Does not start) Immobiliser system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
ECM power source circuit Refer to ECM Power Source Circuit
VC output circuit Refer to VC Output Circuit
Fuel pump control circuit Refer to Fuel Pump Control Circuit
Crankshaft position sensor Refer to ON-VEHICLE INSPECTION
Ignition system Refer to ON-VEHICLE INSPECTION
Valve timing Refer to PROCEDURE - Step 3
Engine cranks normally but difficult to start Fuel pump control circuit Refer to Fuel Pump Control Circuit
Fuel pump for high pressure Refer to ON-VEHICLE INSPECTION
Compression Refer to ON-VEHICLE INSPECTION - Step 9
Engine coolant temperature sensor Refer to INSPECTION
Ignition system Refer to ON-VEHICLE INSPECTION
Intake system Refer to ON-VEHICLE INSPECTION
Throttle body 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
Ignition system Refer to ON-VEHICLE INSPECTION
Fuel line -
Fuel injector for direct injection Refer to INSPECTION
Fuel injector for port injection Refer to INSPECTION
Crankshaft position sensor Refer to ON-VEHICLE INSPECTION
High engine speed (Poor idle) Air conditioning signal circuit Refer to PROBLEM SYMPTOMS TABLE
Throttle body Refer to ON-VEHICLE INSPECTION
Throttle body control -
Engine coolant temperature sensor Refer to INSPECTION
PCV hose Refer to ON-VEHICLE INSPECTION - Step 1
PCV system Refer to ON-VEHICLE INSPECTION
Low engine idle speed (Poor idle) Fuel pump control circuit Refer to Fuel Pump Control Circuit
Fuel pump for high pressure Refer to ON-VEHICLE INSPECTION
Electronic throttle control system Refer to DTC P0120: Throttle / Pedal Position Sensor / Switch "A" Circuit Malfunction; DTC P0121: Throttle / Pedal Position Sensor / Switch "A" Circuit Range / Performance Problem; DTC P0122: Throttle / Pedal Position Sensor / Switch "A" Circuit Low Input; DTC P0123: Throttle / Pedal Position Sensor / Switch "A" Circuit High Input; DTC P0220: Throttle / Pedal Position Sensor / Switch "B" Circuit; DTC P0222: Throttle / Pedal Position Sensor / Switch "B" Circuit Low Input; DTC P0223: Throttle / Pedal Position Sensor / Switch "B" Circuit High Input; DTC P2135: Throttle / Pedal Position Sensor / Switch "A" / "B" Voltage Correlation
Intake system Refer to ON-VEHICLE INSPECTION
PCV hose Refer to ON-VEHICLE INSPECTION - Step 1
Rough idle Compression Refer to ON-VEHICLE INSPECTION - Step 9
Air fuel ratio sensor Refer to ON-VEHICLE INSPECTION
Heated oxygen sensor Refer to ON-VEHICLE INSPECTION
Mass air flow meter Refer to ON-VEHICLE INSPECTION
Ignition system Refer to ON-VEHICLE INSPECTION
Air conditioning signal circuit Refer to PROBLEM SYMPTOMS TABLE
Fuel line (clocked) -
Fuel pump for high pressure Refer to ON-VEHICLE INSPECTION
Electronic throttle control system Refer to DTC P0120: Throttle / Pedal Position Sensor / Switch "A" Circuit Malfunction; DTC P0121: Throttle / Pedal Position Sensor / Switch "A" Circuit Range / Performance Problem; DTC P0122: Throttle / Pedal Position Sensor / Switch "A" Circuit Low Input; DTC P0123: Throttle / Pedal Position Sensor / Switch "A" Circuit High Input; DTC P0220: Throttle / Pedal Position Sensor / Switch "B" Circuit; DTC P0222: Throttle / Pedal Position Sensor / Switch "B" Circuit Low Input; DTC P0223: Throttle / Pedal Position Sensor / Switch "B" Circuit High Input; DTC P2135: Throttle / Pedal Position Sensor / Switch "A" / "B" Voltage Correlation
Intake system Refer to ON-VEHICLE INSPECTION
PCV hose Refer to ON-VEHICLE INSPECTION - Step 1
Hunting (Poor idle) PCV hose Refer to ON-VEHICLE INSPECTION - Step 1
Mass air flow meter Refer to ON-VEHICLE INSPECTION
Air fuel ratio sensor Refer to ON-VEHICLE INSPECTION
Hesitation/Poor acceleration (Poor driveability) Fuel line -
Fuel pump for high pressure Refer to ON-VEHICLE INSPECTION
Mass air flow meter Refer to ON-VEHICLE INSPECTION
Valve timing Refer to PROCEDURE - Step 3
Throttle body Refer to ON-VEHICLE INSPECTION
Knock sensor Refer to INSPECTION
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 for high pressure Refer to ON-VEHICLE INSPECTION
Ignition system Refer to ON-VEHICLE INSPECTION
Fuel injector for port injection Refer to INSPECTION
Fuel injector for direct injection Refer to INSPECTION
Engine stalls soon after starting Mass air flow meter Refer to ON-VEHICLE INSPECTION
Intake system Refer to ON-VEHICLE INSPECTION
Fuel line -
Engine stalls during A/C operation Air conditioning signal circuit (compressor circuit) Refer to PROBLEM SYMPTOMS TABLE
ECM Refer to REMOVAL
Unable/difficult to refuel Refueling valve (canister) Refer to INSPECTION