Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
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 |
|---|---|---|
| Engine does not crank (does not start) | 1. Immobilizer system | SYSTEM DESCRIPTION |
| 2. Starter | INSPECTION | |
| 3. STARTER Relay | INSPECTION | |
| 4. Starter signal circuit | DTC P0617 STARTER RELAY CIRCUIT HIGH | |
| No initial combustion (does not start) | 1. ECM power source circuit | ECM POWER SOURCE CIRCUIT |
| 2. Ignition system | ON-VEHICLE INSPECTION | |
| 3. Fuel pump control circuit | FUEL PUMP CONTROL CIRCUIT | |
| 4. Injector | INSPECTION | |
| 5. Crank angle sensor | - | |
| 6. ECM | - | |
| Difficult to start (engine cranks normally) | 1. Electronic Throttle Control System (ETCS) | THROTTLE BODY |
| 2. Fuel pump control circuit | FUEL PUMP CONTROL CIRCUIT | |
| 3. Ignition system | ON-VEHICLE INSPECTION | |
| 4. Spark plug | INSPECTION | |
| 5. Compression | INSPECTION | |
| 6. Injector | INSPECTION | |
| 7. Crank angle sensor | - | |
| Difficult to start with cold engine | 1. Starter signal circuit | DTC P0617 STARTER RELAY CIRCUIT HIGH |
| 2. Electronic Throttle Control System (ETCS) | THROTTLE BODY | |
| 3. Fuel pump control circuit | FUEL PUMP CONTROL CIRCUIT | |
| 4. Spark plug | INSPECTION | |
| 5. Ignition system | ON-VEHICLE INSPECTION | |
| 6. Injector | INSPECTION | |
| 7. Engine coolant temperature sensor | - | |
| Difficult to start with hot engine | 1. Starter signal circuit | DTC P0617 STARTER RELAY CIRCUIT HIGH |
| 2. Electronic Throttle Control System (ETCS) | THROTTLE BODY | |
| 3. Fuel pump control circuit | FUEL PUMP CONTROL CIRCUIT | |
| 4. Spark plug | INSPECTION | |
| 5. Ignition system | ON-VEHICLE INSPECTION | |
| 6. Injector | INSPECTION | |
| 7. Engine coolant temperature sensor | - | |
| High engine idle speed (poor idling) | 1. Electronic Throttle Control System (ETCS) | THROTTLE BODY |
| 2. ECM power source circuit | ECM POWER SOURCE CIRCUIT | |
| 3. A/C signal circuit (Compressor circuit) | COMPRESSOR CIRCUIT | |
| 4. Acoustic Control Induction System (ACIS) | ACIS CONTROL CIRCUIT | |
| 5. PCV hose | - | |
| 6. ECM | - | |
| Low engine idle speed (poor idling) | 1. Electronic Throttle Control System (ETCS) | THROTTLE BODY |
| 2. ECM power source circuit | ECM POWER SOURCE CIRCUIT | |
| 3. A/C signal circuit (Compressor circuit) | COMPRESSOR CIRCUIT | |
| 4. Acoustic Control Induction System (ACIS) | ACIS CONTROL CIRCUIT | |
| 5. PCV hose | - | |
| 6. Injector | INSPECTION | |
| 7. ECM | - | |
| Rough idling (poor idling) | 1. Electronic Throttle Control System (ETCS) | THROTTLE BODY |
| 2. Injector | INSPECTION | |
| 3. Ignition system | ON-VEHICLE INSPECTION | |
| 4. Compression | INSPECTION | |
| 5. Fuel pump control circuit | FUEL PUMP CONTROL CIRCUIT | |
| 6. Spark plug | INSPECTION | |
| 7. Acoustic Control Induction System (ACIS) | ACIS CONTROL CIRCUIT | |
| 8. PCV hose | - | |
| Hunting (poor idling) | 1. Electronic Throttle Control System (ETCS) | THROTTLE BODY |
| 2. ECM power source circuit | ECM POWER SOURCE CIRCUIT | |
| 3. Fuel pump control circuit | FUEL PUMP CONTROL CIRCUIT | |
| 4. Spark plug | INSPECTION | |
| 5. Ignition system | ON-VEHICLE INSPECTION | |
| 6. Injector | INSPECTION | |
| 7. Acoustic Control Induction System (ACIS) | ACIS CONTROL CIRCUIT | |
| 8. PCV hose | - | |
| Hesitation/Poor acceleration (poor driveability) | 1. Injector | INSPECTION |
| 2. Fuel pump control circuit | FUEL PUMP CONTROL CIRCUIT | |
| 3. Ignition system | ON-VEHICLE INSPECTION | |
| 4. Spark plug | INSPECTION | |
| 5. Air Intake Control System (ACIS) | ACIS CONTROL CIRCUIT | |
| 6. A/T faulty | - | |
| Surging (poor driveability) | 1. Fuel pump control circuit | FUEL PUMP CONTROL CIRCUIT |
| 2. Spark plug | INSPECTION | |
| 3. Ignition system | ON-VEHICLE INSPECTION | |
| 4. Injector | INSPECTION | |
| Engine stalls soon after starting | 1. Fuel pump control circuit | FUEL PUMP CONTROL CIRCUIT |
| 2. Electronic Throttle Control System (ETCS) | THROTTLE BODY | |
| 3. Crank angle sensor | - | |
| 4. Spark plug | INSPECTION | |
| 5. Ignition system | ON-VEHICLE INSPECTION | |
| 6. Injector | INSPECTION | |
| Engine stalls during A/C operation | 1. A/C signal circuit (Compressor circuit) | COMPRESSOR CIRCUIT |
| 2. ECM | - | |
| Unable/difficult to refuel | Refueling valve (canister) | INSPECTION |
| Engine vibrates frequently when idling (Active Control) | Active control engine mount circuit | ACTIVE CONTROL ENGINE MOUNT SYSTEM |
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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