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Home >> Lexus >> 2012 >> IS 250C Standard Trans >> Repair and Diagnosis >> Engine Performance >> Testing & Diagnosis >> Engine Control System (4GR-FSE) (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
Cranking holding function circuit Refer to Cranking Holding Function Circuit
Smart access system with push button start Refer to PROBLEM SYMPTOMS TABLE
Starter assembly Refer to INSPECTION
VC output circuit (ECM 5 V output) Refer to VC Output Circuit
No initial combustion (Does not start) Immobilizer system Refer to PROBLEM SYMPTOMS TABLE
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
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 for high pressure Refer to ON-VEHICLE 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 10
Intake system Refer to ON-VEHICLE INSPECTION - Step 1
Throttle body assembly Refer to INSPECTION
Cold start injector circuit Refer to Cold Start Injector Circuit
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 for high pressure Refer to ON-VEHICLE INSPECTION
Fuel line Refer to ON-VEHICLE INSPECTION
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 PROBLEM SYMPTOMS TABLE
Throttle body assembly Refer to INSPECTION
Throttle body assembly control Refer to ON-VEHICLE INSPECTION
Engine coolant temperature sensor Refer to INSPECTION
PCV hose Refer to ON-VEHICLE INSPECTION
PCV system Refer to 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 body assembly Refer to INSPECTION
Throttle body assembly control Refer to ON-VEHICLE INSPECTION
Intake system Refer to ON-VEHICLE INSPECTION - Step 1
ACIS control circuit Refer to ACIS Control Circuit
PCV hose Refer to ON-VEHICLE INSPECTION
PCV system Refer to INSPECTION
Engine stalls on deceleration Idle speed (refer to "Low engine speed") Refer to ON-VEHICLE INSPECTION - Step 9
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 Refer to ON-VEHICLE INSPECTION
Ignition system Refer to ON-VEHICLE INSPECTION
Air conditioning signal circuit Refer to PROBLEM SYMPTOMS TABLE
Fuel line Refer to ON-VEHICLE INSPECTION
Valve timing Refer to PROCEDURE - Step 4
Fuel pump for low or high pressure Refer to ON-VEHICLE INSPECTION - Step 1
Intake system Refer to ON-VEHICLE INSPECTION - Step 1
ACIS control circuit Refer to ACIS Control Circuit
PCV hose Refer to ON-VEHICLE INSPECTION
PCV system Refer to INSPECTION
Hunting (Poor idle) PCV hose Refer to ON-VEHICLE INSPECTION
PCV system Refer to INSPECTION
Mass air flow meter 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 PROBLEM SYMPTOMS TABLE
ECM Refer to REMOVAL
Cold start injector circuit Refer to Cold Start Injector Circuit
Hesitation/Poor acceleration (Poor driveability) Fuel line Refer to ON-VEHICLE INSPECTION
Fuel pump for low or high pressure Refer to ON-VEHICLE INSPECTION - Step 1
Valve timing Refer to PROCEDURE - Step 4
Mass air flow meter Refer to ON-VEHICLE INSPECTION
Throttle body assembly Refer to INSPECTION
Knock control sensor Refer to INSPECTION
Brake override system Refer to Brake Override System
Surging (Poor driveability) Fuel line Refer to ON-VEHICLE INSPECTION
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 assembly Refer to INSPECTION
Engine stalls soon after starting Mass air flow meter Refer to ON-VEHICLE INSPECTION
Intake system Refer to ON-VEHICLE INSPECTION - Step 1
Fuel line Refer to ON-VEHICLE INSPECTION
Cold start injector circuit Refer to Cold Start Injector Circuit
Unable/difficult to refuel Fuel system (canister, refueling valve, roll over valve, fuel tank, etc.) -