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Home >> Lexus >> 2011 >> IS 350 Base, RWD >> 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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Use the table below to help determine the cause of the problem. The potential cases 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.

SFI SYSTEM

Symptom Suspected Area See
Engine does not crank (Does not start) 1. Immobilizer System Refer to PROBLEM SYMPTOMS TABLE
2. ECM power source circuit Refer to ECM Power Source Circuit
3. VC output circuit Refer to VC Output Circuit
4. Cranking holding function circuit Refer to Cranking Holding Function Circuit
5. Starter Refer to INSPECTION
No initial combustion (Does not start) 1. ECM power source circuit Refer to ECM Power Source Circuit
2. Fuel pump control circuit Refer to Fuel Pump Control Circuit
3. ECM Refer to REMOVAL
Engine cranks normally but difficult to start 1. Fuel pump control circuit Refer to Fuel Pump Control Circuit
2.Fuel pump for high pressure Refer to ON-VEHICLE INSPECTION
3. Compression Refer to ON-VEHICLE INSPECTION - Step 9
4. ECM power source circuit Refer to ECM Power Source Circuit
Difficult to start with cold engine 1. Cranking holding function circuit Refer to Cranking Holding Function Circuit
2. Ignition system Refer to ON-VEHICLE INSPECTION
3. Spark plug Refer to ON-VEHICLE INSPECTION - Step 2
4. Fuel pump control circuit Refer to Fuel Pump Control Circuit
5. Fuel pump for high pressure Refer to ON-VEHICLE INSPECTION
6. Fuel injector for direct injection Refer to INSPECTION
7. Fuel injector for port injection Refer to INSPECTION
Difficult to start with worm engine 1. Cranking holding function circuit Refer to Cranking Holding Function Circuit
2. Fuel injector for port injection Refer to INSPECTION
3. Fuel injector for direct injection Refer to INSPECTION
4. Ignition system Refer to ON-VEHICLE INSPECTION
5. Spark plug Refer to ON-VEHICLE INSPECTION - Step 2
6. Fuel pump control circuit Refer to Fuel Pump Control Circuit
7. Fuel pump for high pressure Refer to ON-VEHICLE INSPECTION
High engine idle speed (Poor idling) 1. ECM power source circuit Refer to ECM Power Source Circuit
2. A/C signal circuit (compressor circuit) Refer to Air Conditioning Compressor Magnetic Clutch Circuit
3. Electronic throttle control system Refer to ON-VEHICLE INSPECTION
4. Air induction system -
5. PCV hose Refer to ON-VEHICLE INSPECTION
Low engine idle speed (Poor idling) 1. A/C signal circuit (compressor circuit) Refer to Air Conditioning Compressor Magnetic Clutch Circuit
2. Fuel pump control circuit Refer to Fuel Pump Control Circuit
3. Fuel pump for high pressure Refer to ON-VEHICLE INSPECTION
4. Electronic throttle control system Refer to ON-VEHICLE INSPECTION
5. Air induction system -
6. PCV hose Refer to ON-VEHICLE INSPECTION
Rough idling (Poor idling) 1. Compression Refer to ON-VEHICLE INSPECTION - Step 9
2. Fuel pump control circuit Refer to Fuel Pump Control Circuit
3. Fuel pump for high pressure Refer to ON-VEHICLE INSPECTION
4. Electronic throttle control system Refer to ON-VEHICLE INSPECTION
5. Air induction system -
6. PCV hose Refer to ON-VEHICLE INSPECTION
Hunting (Poor idling) 1. ECM power source circuit Refer to ECM Power Source Circuit
2. Fuel pump control circuit Refer to Fuel Pump Control Circuit
3. Fuel pump for high pressure Refer to ON-VEHICLE INSPECTION
4. Spark plug Refer to ON-VEHICLE INSPECTION - Step 2
5. Ignition system Refer to ON-VEHICLE INSPECTION
6. Fuel injector for port injection Refer to INSPECTION
7. Fuel injector for direct injection Refer to INSPECTION
8. Electronic throttle control system Refer to ON-VEHICLE INSPECTION
9. Air induction system -
10. PCV hose Refer to ON-VEHICLE INSPECTION
Hesitation/ Poor acceleration (Poor driveability) 1. Fuel pump control circuit Refer to Fuel Pump Control Circuit
2. Fuel pump for high pressure Refer to ON-VEHICLE INSPECTION
3. Spark plug Refer to ON-VEHICLE INSPECTION - Step 2
4. Ignition system Refer to ON-VEHICLE INSPECTION
5. Fuel injector for port injection Refer to INSPECTION
6. Fuel injector for direct injection Refer to INSPECTION
7. Brake override system Refer to Brake Override System
Surging (Poor driveability) 1. Spark plug Refer to ON-VEHICLE INSPECTION - Step 2
2. Fuel pump control circuit Refer to Fuel Pump Control Circuit
3. Fuel pump for high pressure Refer to ON-VEHICLE INSPECTION
4. Ignition system Refer to ON-VEHICLE INSPECTION
5. Fuel injector for port injection Refer to INSPECTION
6. Fuel injector for direct injection Refer to INSPECTION
Engine stalls soon after starting 1. Fuel pump control circuit Refer to Fuel Pump Control Circuit
2. Fuel pump for high pressure Refer to ON-VEHICLE INSPECTION
3. Spark plug Refer to ON-VEHICLE INSPECTION - Step 2
4. Ignition system Refer to ON-VEHICLE INSPECTION
5. Fuel injector for port injection Refer to INSPECTION
6. Fuel injector for direct injection Refer to INSPECTION
Engine stalls during A/C operation 1. A/C signal circuit (Compressor circuit) Refer to Air Conditioning Compressor Magnetic Clutch Circuit
2. ECM Refer to REMOVAL
Unable/difficult refuel 1. Refueling valve (canister) -