LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2008 >> RX 350 FWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - SFI System Description, Diagnostic Introduction, Diagnostic Trouble Code Chart >> SFI System >> Problem Symptoms Table
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Problem Symptoms Table

SFI SYSTEM 

PROBLEM SYMPTOMS

Symptom Suspected Area
Engine does not crank (does not start) 1. Immobilizer system
2. Starter
3. STARTER Relay
4. Starter signal circuit
No initial combustion (does not start) 1. ECM power source circuit
2. Ignition system
3. Fuel pump control circuit
4. Injector
5. Crank angle sensor
6. ECM
Difficult to start (engine cranks normally) 1. Electronic Throttle Control System (ETCS)
2. Fuel pump control circuit
3. Ignition system
4. Spark plug
5. Compression
6. Injector
7. Crank angle sensor
Difficult to start with cold engine 1. Starter signal circuit
2. Electronic Throttle Control System (ETCS)
3. Fuel pump control circuit
4. Spark plug
5. Ignition system
6. Injector
7. Engine coolant temperature sensor
Difficult to start with hot engine 1. Starter signal circuit
2. Electronic Throttle Control System (ETCS)
3. Fuel pump control circuit
4. Spark plug
5. Ignition system
6. Injector
7. Engine coolant temperature sensor
High engine idle speed (poor idling) 1. Electronic Throttle Control System (ETCS)
2. ECM power source circuit
3. A/C signal circuit (Compressor circuit)
4. Acoustic Control Induction System (ACIS)
5. PCV hose
6. ECM
Low engine idle speed (poor idling) 1. Electronic Throttle Control System (ETCS)
2. ECM power source circuit
3. A/C signal circuit (Compressor circuit)
4. Acoustic Control Induction System (ACIS)
5. PCV hose
6. Injector
7. ECM
Rough idling (poor idling) 1. Electronic Throttle Control System (ETCS)
2. Injector
3. Ignition system
4. Compression
5. Fuel pump control circuit
6. Spark plug
7. Acoustic Control Induction System (ACIS)
8. PCV hose
Hunting (poor idling) 1. Electronic Throttle Control System (ETCS)
2. ECM power source circuit
3. Fuel pump control circuit
4. Spark plug
5. Ignition system
6. Injector
7. Acoustic Control Induction System (ACIS)
8. PCV hose
Hesitation/Poor acceleration (poor driveability) 1. Injector
2. Fuel pump control circuit
3. Ignition system
4. Spark plug
5. Air Intake Control System (AICS)
6. A/T faulty
Surging (poor driveability) 1. Fuel pump control circuit
2. Spark plug
3. Ignition system
4. Injector
Engine stalls soon after starting 1. Fuel pump control circuit
2. Electronic Throttle Control System (ETCS)
3. Crank angle sensor
4. Spark plug
5. Ignition system
6. Injector
Engine stalls during A/C operation 1. A/C signal circuit (Compressor circuit)
2. ECM
Unable/difficult to refuel Refueling valve (canister)
Engine vibrates frequently when idling (Active Control Engine Mount System) Active control engine mount circuit