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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 the problem cannot be identified through a basic inspection, troubleshoot according to the priority order indicated in the table below.

SFI system 

SFI SYSTEM - PROBLEM SYMPTOMS CHART

Symptom Suspected Area See
Engine does not crank (Does not start) 1. Immobiliser system SYSTEM DESCRIPTION
2. Starter INSPECTION
3. STARTER relay STARTER RELAY
No initial combustion (Does not start) 1. ECM power source circuit ECM POWER SOURCE CIRCUIT 
2. ECM VC output circuit VC OUTPUT CIRCUIT 
3. Fuel pump control circuit FUEL PUMP CONTROL CIRCUIT 
4. ECM ECM 
Engine cranks normally but difficult to start 1. Fuel pump control circuit FUEL PUMP CONTROL CIRCUIT 
2. Compression ON-VEHICLE INSPECTION
Difficult to start with cold engine 1. Start signal circuit SYSTEM DIAGRAM
2. Fuel pump control circuit FUEL PUMP CONTROL CIRCUIT 
3. Spark plug ON-VEHICLE INSPECTION
4. Ignition system ON-VEHICLE INSPECTION
5. Injector INSPECTION
Difficult to start with warm engine 1. Start signal circuit SYSTEM DIAGRAM
2. Fuel pump control circuit FUEL PUMP CONTROL CIRCUIT 
3. Spark plug ON-VEHICLE INSPECTION
4. Ignition system ON-VEHICLE INSPECTION
5. Injector INSPECTION
High engine idling speed (Poor idling) 1. A/C signal circuit (compressor circuit) -
2. ECM power source circuit ECM POWER SOURCE CIRCUIT 
3. Electronic throttle control system DTC P2102 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT LOW; DTC P2103 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT HIGH 
4. Air induction system -
5. PCV hose -
Low engine idling speed (Poor idling) 1. A/C signal circuit (compressor circuit) -
2. Fuel pump control circuit FUEL PUMP CONTROL CIRCUIT 
3. Electronic throttle control system DTC P2102 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT LOW; DTC P2103 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT HIGH 
4. Air induction system -
5. PCV hose -
Rough Idling (Poor idling) 1. Compression ON-VEHICLE INSPECTION
2. Fuel pump control circuit FUEL PUMP CONTROL CIRCUIT 
3. Electronic throttle control system DTC P2102 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT LOW; DTC P2103 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT HIGH 
4. Air induction system -
5. PCV hose -
Hunting (Poor idling) 1. ECM power source circuit ECM POWER SOURCE CIRCUIT 
2. Fuel pump control circuit FUEL PUMP CONTROL CIRCUIT 
3. Spark plug ON-VEHICLE INSPECTION
4. Ignition system ON-VEHICLE INSPECTION
5. Injector INSPECTION
6. Electronic throttle control system DTC P2102 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT LOW; DTC P2103 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT HIGH 
7. Air induction system -
8. PCV hose -
Hesitation/Poor acceleration (Poor driveability) 1. Fuel pump control circuit FUEL PUMP CONTROL CIRCUIT 
2. A/T faulty* SYSTEM DESCRIPTION
3. Spark plug ON-VEHICLE INSPECTION
4. Ignition system ON-VEHICLE INSPECTION
5. Injector REMOVAL
Surging (Poor driveability) 1. Fuel pump control circuit FUEL PUMP CONTROL CIRCUIT 
3. Spark plug ON-VEHICLE INSPECTION
4. Ignition system ON-VEHICLE INSPECTION
5. Injector INSPECTION
Engine stalls soon after starting 1. Fuel pump control circuit FUEL PUMP CONTROL CIRCUIT 
2. Spark plug ON-VEHICLE INSPECTION
3. Ignition system ON-VEHICLE INSPECTION
4. Injector INSPECTION
Engine stalls during A/C operation 1. A/C signal circuit (compressor circuit) -
2. ECM ECM 
Unable/difficult to refuel Refueling valve (canister) -