LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Toyota >> 2008 >> Sienna CE >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - SFI System Precautions And Diagnostics Introductions, Diagnostic Trouble Code Chart >> SFI System >> Problem Symptoms Table
April 5, 2026: LEMON Manuals is launched! Read the announcement.

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 

SYMPTOMS REFERENCE

Symptom Suspected Area See Procedure
Engine does not crank (does not start) 1. Immobilizer system SYSTEM DESCRIPTION
2. Starter DISASSEMBLY
3. STARTER Relay STARTER RELAY
4. Cranking holding function circuit CRANKING HOLDING FUNCTION CIRCUIT
No initial combustion (does not start) 1. ECM power source circuit ECM POWER SOURCE CIRCUIT
2. Ignition system COMPONENTS
3. Fuel pump control circuit FUEL PUMP CONTROL CIRCUIT
4. Injector FUEL INJECTOR
5. VC output circuit VC OUTPUT CIRCUIT
6. ECM ECM
Difficult to start (engine cranks normally) 1. Electronic Throttle Control System (ETCS) DTC P2102 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT LOW; DTC P2103 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT HIGH
2. Fuel pump control circuit FUEL PUMP CONTROL CIRCUIT
3. Ignition system COMPONENTS
4. Spark plug ON-VEHICLE INSPECTION
5. Compression ON-VEHICLE INSPECTION
6. Injector FUEL INJECTOR
7. VC output circuit VC OUTPUT CIRCUIT
Difficult to start with cold engine 1. Cranking holding function circuit CRANKING HOLDING FUNCTION CIRCUIT
2. Electronic Throttle Control System (ETCS) DTC P2102 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT LOW; DTC P2103 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT HIGH
3. Fuel pump control circuit FUEL PUMP CONTROL CIRCUIT
4. Spark plug ON-VEHICLE INSPECTION
5. Ignition system COMPONENTS
6. Injector FUEL INJECTOR
7. Engine coolant temperature sensor ENGINE COOLANT TEMPERATURE SENSOR
Difficult to start with hot engine 1. Cooling fan system COOLING FAN SYSTEM
2. Cranking holding function circuit CRANKING HOLDING FUNCTION CIRCUIT
3. Electronic Throttle Control System (ETCS) DTC P2102 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT LOW; DTC P2103 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT HIGH
4. Fuel pump control circuit FUEL PUMP CONTROL CIRCUIT
5. Spark plug ON-VEHICLE INSPECTION
6. Ignition system COMPONENTS
7. Injector FUEL INJECTOR
8. Engine coolant temperature sensor ENGINE COOLANT TEMPERATURE SENSOR
High engine idle speed (poor idling) 1. Electronic Throttle Control System (ETCS) DTC P2102 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT LOW; DTC P2103 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT HIGH
2. ECM power source circuit ECM POWER SOURCE CIRCUIT
3. A/C signal circuit (Compressor circuit) -
4. Acoustic Control Induction System (ACIS) ACIS CONTROL CIRCUIT
5. PCV hose ON-VEHICLE INSPECTION
6. ECM ECM
Low engine idle speed (poor idling) 1. Electronic Throttle Control System (ETCS) DTC P2102 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT LOW; DTC P2103 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT HIGH
2. ECM power source circuit ECM POWER SOURCE CIRCUIT
3. A/C signal circuit (Compressor circuit) -
4. Acoustic Control Induction System (ACIS) ACIS CONTROL CIRCUIT
5. PCV hose ON-VEHICLE INSPECTION
6. Injector FUEL INJECTOR
7. ECM ECM
Rough idling (poor idling) 1. Electronic Throttle Control System (ETCS) DTC P2102 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT LOW; DTC P2103 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT HIGH
2. Injector FUEL INJECTOR
3. Ignition system COMPONENTS
4. Compression ON-VEHICLE INSPECTION
5. Fuel pump control circuit FUEL PUMP CONTROL CIRCUIT
6. Spark plug ON-VEHICLE INSPECTION
7. Acoustic Control Induction System (ACIS) ACIS CONTROL CIRCUIT
8. PCV hose ON-VEHICLE INSPECTION
Hunting (poor idling) 1. Electronic Throttle Control System (ETCS) DTC P2102 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT LOW; DTC P2103 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT HIGH
2. ECM power source circuit ECM POWER SOURCE CIRCUIT
3. Fuel pump control circuit FUEL PUMP CONTROL CIRCUIT
4. Spark plug ON-VEHICLE INSPECTION
5. Ignition system COMPONENTS
6. Injector FUEL INJECTOR
7. Acoustic Control Induction System (ACIS) ACIS CONTROL CIRCUIT
8. PCV hose ON-VEHICLE INSPECTION
Hesitation/Poor acceleration (poor driveability) 1. Injector FUEL INJECTOR
2. Fuel pump control circuit FUEL PUMP CONTROL CIRCUIT
3. Ignition system COMPONENTS
4. Spark plug ON-VEHICLE INSPECTION
5. Air Intake Control System (AICS) ACIS CONTROL CIRCUIT
6. A/T faulty (U151E) SYSTEM DESCRIPTION
7. A/T faulty (U151F) SYSTEM DESCRIPTION
Surging (poor driveability) 1. Fuel pump control circuit FUEL PUMP CONTROL CIRCUIT
2. Spark plug ON-VEHICLE INSPECTION
3. Ignition system COMPONENTS
4. Injector FUEL INJECTOR
Engine stalls soon after starting 1. Fuel pump control circuit FUEL PUMP CONTROL CIRCUIT
2. Electronic Throttle Control System (ETCS) DTC P2102 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT LOW; DTC P2103 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT HIGH
3. Crankshaft position sensor CRANKSHAFT POSITION SENSOR
4. Spark plug ON-VEHICLE INSPECTION
5. Ignition system COMPONENTS
6. Injector FUEL INJECTOR
Engine stalls during A/C operation 1. A/C signal circuit (Compressor circuit) -
2. ECM ECM
Unable/difficult to refuel Refueling valve (canister) -
Engine vibrates frequently when idling (Active Control) Active control engine mount circuit ACTIVE CONTROL ENGINE MOUNT SYSTEM