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Home >> Toyota >> 2010 >> Sienna XLE, FWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control (SFI) System (Diagnostics - Introduction) >> SFI System >> Problem Symptoms Table >> Problem Symptoms Table
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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 Reference
Engine does not crank (does not start) Immobilizer system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Starter Refer to INSPECTION
STARTER Relay Refer to ON-VEHICLE INSPECTION
Cranking holding function circuit Refer to Cranking Holding Function Circuit
No initial combustion (does not start) ECM power source circuit Refer to ECM Power Source Circuit
Ignition system Refer to ON-VEHICLE INSPECTION
Fuel pump control circuit Refer to Fuel Pump Control Circuit
Injector Refer to INSPECTION
VC output circuit Refer to VC Output Circuit
ECM -
Difficult to start (engine cranks normally) Electronic Throttle Control System (ETCS) Refer to INSPECTION
Fuel pump control circuit Refer to Fuel Pump Control Circuit
Ignition system Refer to ON-VEHICLE INSPECTION
Spark plug Refer to ON-VEHICLE INSPECTION - Step 2
Compression Refer to ON-VEHICLE INSPECTION - Step 9
Injector Refer to INSPECTION
VC output circuit Refer to VC Output Circuit
Difficult to start with cold engine Cranking holding function circuit Refer to Cranking Holding Function Circuit
Electronic Throttle Control System (ETCS) Refer to INSPECTION
Fuel pump control circuit Refer to Fuel Pump Control Circuit
Spark plug Refer to ON-VEHICLE INSPECTION - Step 2
Ignition system Refer to ON-VEHICLE INSPECTION
Injector Refer to INSPECTION
Engine coolant temperature sensor Refer to INSPECTION - Step 1
Difficult to start with hot engine Cooling fan system Refer to ON-VEHICLE INSPECTION
Cranking holding function circuit Refer to Cranking Holding Function Circuit
Electronic Throttle Control System (ETCS) Refer to INSPECTION
Fuel pump control circuit Refer to Fuel Pump Control Circuit
Spark plug Refer to ON-VEHICLE INSPECTION - Step 2
Ignition system Refer to ON-VEHICLE INSPECTION
Injector Refer to INSPECTION - Step 1
Engine coolant temperature sensor Refer to INSPECTION - Step 1
High engine idle speed (poor idling) Electronic Throttle Control System (ETCS) Refer to INSPECTION
ECM power source circuit Refer to ECM Power Source Circuit
A/C signal circuit (Compressor circuit) -
Acoustic Control Induction System (ACIS) Refer to ACIS Control Circuit
PCV hose -
ECM -
Low engine idle speed (poor idling) Electronic Throttle Control System (ETCS) Refer to INSPECTION
ECM power source circuit Refer to ECM Power Source Circuit
A/C signal circuit (Compressor circuit) -
Acoustic Control Induction System (ACIS) Refer to ACIS Control Circuit
PCV hose -
Injector Refer to INSPECTION
ECM -
Rough idling (poor idling) Electronic Throttle Control System (ETCS) Refer to INSPECTION
Injector Refer to INSPECTION
Ignition system Refer to ON-VEHICLE INSPECTION
Compression Refer to ON-VEHICLE INSPECTION - Step 9
Fuel pump control circuit Refer to Fuel Pump Control Circuit
Spark plug Refer to ON-VEHICLE INSPECTION - Step 2
Acoustic Control Induction System (ACIS) Refer to ACIS Control Circuit
PCV hose -
Hunting (poor idling) Electronic Throttle Control System (ETCS) Refer to INSPECTION
ECM power source circuit Refer to ECM Power Source Circuit
Fuel pump control circuit Refer to Fuel Pump Control Circuit
Spark plug Refer to ON-VEHICLE INSPECTION - Step 2
Ignition system Refer to ON-VEHICLE INSPECTION
Injector Refer to INSPECTION
Acoustic Control Induction System (ACIS) Refer to ACIS Control Circuit
PCV hose -
Hesitation/Poor acceleration (poor driveability) Injector Refer to INSPECTION - Step 1
Fuel pump control circuit Refer to Fuel Pump Control Circuit
Ignition system Refer to ON-VEHICLE INSPECTION
Spark plug Refer to ON-VEHICLE INSPECTION - Step 2
Air Intake Control System (AICS) Refer to ACIS Control Circuit
A/T faulty (U151E) Refer to HOW TO PROCEED WITH TROUBLESHOOTING
A/T faulty (U151F) Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Surging (poor driveability) Fuel pump control circuit Refer to Fuel Pump Control Circuit
Spark plug Refer to ON-VEHICLE INSPECTION - Step 2
Ignition system Refer to ON-VEHICLE INSPECTION
Injector Refer to INSPECTION
Engine stalls soon after starting Fuel pump control circuit Refer to Fuel Pump Control Circuit
Electronic Throttle Control System (ETCS) Refer to INSPECTION
Crankshaft position sensor Refer to INSPECTION
Spark plug Refer to ON-VEHICLE INSPECTION - Step 2
Ignition system Refer to ON-VEHICLE INSPECTION
Injector Refer to INSPECTION
Engine stalls during A/C operation A/C signal circuit (Compressor circuit) -
ECM -
Unable/difficult to refuel Refueling valve (canister) -
Engine vibrates frequently when idling (Active Control) Active control engine mount circuit Refer to Active Control Engine Mount System