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Problem Symptoms Table

HINT: 

When a malfunction is not confirmed by a DTC (Diagnostic Trouble Code) check and the cause of problem cannot be identified through a basic inspection, troubleshoot according to the priority order indicated in the table below.

SFI SYSTEM

Symptom Suspected Area See
w/o Smart Key System: Engine does not crank (Does not start) 1. Battery Refer to ON-VEHICLE INSPECTION - Step 1
2. VC output circuit (ECM 5 V output) Refer to VC Output Circuit
3. Starter signal circuit Refer to DTC P0617: Starter Relay Circuit High
4. Starter Refer to INSPECTION
5. ST relay Refer to ON-VEHICLE INSPECTION
6. ECM power source circuit Refer to ECM Power Source Circuit
7. ECM Refer to REMOVAL
w/ Smart Key System: Engine does not crank (Does not start) 1. Battery Refer to ON-VEHICLE INSPECTION - Step 1
2. Smart key system Refer to PROBLEM SYMPTOMS TABLE
3. VC output circuit (ECM 5 V output) Refer to VC Output Circuit
4. Cranking holding function circuit Refer to Cranking Holding Function Circuit
6. Starter Refer to INSPECTION
7. ST relay Refer to ON-VEHICLE INSPECTION
8. ECM power source circuit Refer to ECM Power Source Circuit
9. ECM Refer to REMOVAL
No initial combustion (Does not start) 1. Immobiliser system Refer to PROBLEM SYMPTOMS TABLE
2. ECM power source circuit Refer to ECM Power Source Circuit
3. VC output circuit (ECM 5 V output) Refer to VC Output Circuit
4. Ignition system Refer to ON-VEHICLE INSPECTION
5. Fuel pump control circuit Refer to Fuel Pump Control Circuit
6. Injector Refer to INSPECTION
7. Crankshaft position sensor Refer to INSPECTION
8. ECM Refer to REMOVAL
Engine cranks normally but difficult to start 1. Electronic Throttle Control System (ETCS) Refer to ON-VEHICLE INSPECTION
2. Fuel pump control circuit Refer to Fuel Pump Control Circuit
3. Ignition system Refer to ON-VEHICLE INSPECTION
4. Spark plug Refer to INSPECTION - Step 1
5. Compression Refer to ON-VEHICLE INSPECTION - Step 4
6. Injector Refer to INSPECTION
7. Crankshaft position sensor Refer to INSPECTION
Difficult to start with cold engine 1. Starter signal circuit (w/o smart key system) Refer to DTC P0617: Starter Relay Circuit High
2. Cranking holding function circuit (w/ smart key system) Refer to Cranking Holding Function Circuit
3. Electronic Throttle Control System (ETCS) Refer to ON-VEHICLE INSPECTION
4. Fuel pump control circuit Refer to Fuel Pump Control Circuit
5. Spark plug Refer to INSPECTION - Step 1
6. Ignition system Refer to ON-VEHICLE INSPECTION
7. Injector Refer to INSPECTION
8. Engine coolant temperature sensor Refer to INSPECTION
Difficult to start with warm engine 1. Starter signal circuit (w/o smart key system) Refer to DTC P0617: Starter Relay Circuit High
2. Cranking holding function circuit (w/ smart key system) Refer to Cranking Holding Function Circuit
3. Electronic Throttle Control System (ETCS) Refer to ON-VEHICLE INSPECTION
4. Fuel pump control circuit Refer to Fuel Pump Control Circuit
5. Spark plug Refer to INSPECTION - Step 1
6. Ignition system Refer to ON-VEHICLE INSPECTION
7. Injector Refer to INSPECTION
8. Engine coolant temperature sensor Refer to INSPECTION
High engine idling speed 1. Electronic Throttle Control System (ETCS) Refer to ON-VEHICLE INSPECTION
2. ECM power source circuit Refer to ECM Power Source Circuit
3. A/C signal circuit (Compressor circuit) -
4. Acoustic Control Induction System (ACIS) Refer to ACIS Control Circuit
5. PCV hose Refer to ON-VEHICLE INSPECTION - Step 5
6. ECM Refer to REMOVAL
Low engine idling speed (Poor idling) 1. Electronic Throttle Control System (ETCS) Refer to ON-VEHICLE INSPECTION
2. ECM power source circuit Refer to ECM Power Source Circuit
3. A/C signal circuit (Compressor circuit) -
4. Acoustic Control Induction System (ACIS) Refer to ACIS Control Circuit
5. PCV hose Refer to ON-VEHICLE INSPECTION - Step 5
6. Injector Refer to INSPECTION
7. ECM Refer to REMOVAL
Rough idling (Poor idling) 1. Electronic Throttle Control System (ETCS) Refer to ON-VEHICLE INSPECTION
2. Injector Refer to INSPECTION
3. Ignition system Refer to ON-VEHICLE INSPECTION
4. Compression Refer to ON-VEHICLE INSPECTION - Step 4
5. Fuel pump control circuit Refer to Fuel Pump Control Circuit
6. Spark plug Refer to INSPECTION - Step 1
7. Acoustic Control Induction System (ACIS) Refer to ACIS Control Circuit
8. PCV hose Refer to ON-VEHICLE INSPECTION - Step 5
Hunting (Poor idling) 1. Electronic Throttle Control System (ETCS) Refer to ON-VEHICLE INSPECTION
2. ECM power source circuit Refer to ECM Power Source Circuit
3. Fuel pump control circuit Refer to Fuel Pump Control Circuit
4. Spark plug Refer to INSPECTION - Step 1
5. Ignition system Refer to ON-VEHICLE INSPECTION
6. Injector Refer to INSPECTION
7. Acoustic Control Induction System (ACIS) Refer to ACIS Control Circuit
8. PCV hose Refer to ON-VEHICLE INSPECTION - Step 5
Hesitation/Poor acceleration (Poor driveability) 1. Injector Refer to INSPECTION
2. Fuel pump control circuit Refer to Fuel Pump Control Circuit
3. Ignition system Refer to ON-VEHICLE INSPECTION
4. Spark plug Refer to INSPECTION - Step 1
5. Air Intake Control System (AICS) Refer to Air Intake Control Circuit
6. A/T faulty Refer to HOW TO PROCEED WITH TROUBLESHOOTING
7. Brake override system Refer to Brake Override System
Surging (Poor driveability) 1. Fuel pump control circuit Refer to Fuel Pump Control Circuit
2. Spark plug Refer to INSPECTION - Step 1
3. Ignition system Refer to ON-VEHICLE INSPECTION
4. Injector Refer to INSPECTION
Engine stalls soon after starting 1. Fuel pump control circuit Refer to Fuel Pump Control Circuit
2. Electronic Throttle Control System (ETCS) Refer to ON-VEHICLE INSPECTION
3. Crankshaft position sensor Refer to INSPECTION
4. Spark plug Refer to INSPECTION - Step 1
5. Ignition system Refer to ON-VEHICLE INSPECTION
6. Injector Refer to INSPECTION
Engine stalls during A/C operation 1. A/C signal circuit -
2. ECM Refer to REMOVAL
Unable/difficult to refuel Fuel system (canister, refueling valve, roll-over valve, fuel tank, etc.) -
Engine vibrates frequently when idling (Active Control engine Mount (ACM) system does not operate) Active control engine mount circuit Refer to Active Control Engine Mount System