1ar-fe Engine Control

Problem Symptoms Table

~3min read
PROBLEM SYMPTOMS TABLE

HINT:

  • Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table. Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.
  • Inspect the fuses and relays related to this system before inspecting the suspected areas below.
SFI System

Symptom

Suspected Area

See page

Engine does not crank (Does not start)

Battery

Starter

VC output circuit (ECM 5 V output)

Starter signal circuit

No initial combustion (Does not start)

Engine immobiliser system (w/ smart key system)

Engine immobiliser system (w/o smart key system)

ECM power source circuit

Crankshaft position sensor

Ignition system

Fuel pump control circuit

Fuel injector circuit

Valve timing

VC output circuit (ECM 5 V output)

Camshaft position sensor

Starter signal circuit

ECM

No. 1 valve rocker arm sub-assembly*

Engine cranks normally but difficult to start

Fuel pump control circuit

Fuel pump

Fuel injector circuit

Engine coolant temperature sensor

Intake system

Ignition system

Spark plug

Throttle body

Compression

Starter signal circuit

ECM power source circuit

No. 1 valve rocker arm sub-assembly*

Incomplete intermittent combustion occurs (Does not start)

Fuel pump control circuit

Fuel pump

Ignition circuit

Ignition system

Fuel injector circuit

ECM power source circuit

Crankshaft position sensor

Valve timing

Camshaft position sensor

High engine speed

Throttle body

Intake system

A/C signal circuit

ECM power source circuit

Engine coolant temperature sensor

PCV valve and hose

Acoustic Control Induction System (ACIS)

Low engine speed (Poor idle)

Throttle body

A/C signal circuit

Fuel pump control circuit

Fuel pump

Intake system

PCV valve and hose

Rough idle

Compression

Ignition system

Spark plug

Fuel injector circuit

ECM power source circuit

Fuel pump control circuit

Fuel pump

Throttle body

Intake system

PCV valve and hose

Air fuel ratio sensor

Heated oxygen sensor

Mass air flow meter

ACIS control circuit

Tumble Control Valve (TCV)

No. 1 valve rocker arm sub-assembly*

External part malfunction (Increase in load: A/C system, etc.)

-

Hunting (Poor idle)

Throttle body

Intake system

PCV valve and hose

Air fuel ratio sensor

Mass air flow meter

ACIS control circuit

Tumble Control Valve (TCV)

Hesitation/poor acceleration

Fuel pump control circuit

Fuel pump

Spark plug

Ignition system

Fuel injector circuit

ECM power source circuit

Mass air flow meter

Throttle body

Intake system

Valve timing

Compression

Brake override system

No. 1 valve rocker arm sub-assembly*

Surging (Poor driveability)

Spark plug

Fuel pump control circuit

Fuel pump

Ignition system

Fuel injector circuit

ECM power source circuit

Mass air flow meter

Variable Valve Timing (VVT) system

Compression

No. 1 valve rocker arm sub-assembly*

Engine stalls soon after starting

Fuel pump control circuit

Fuel pump

Spark plug

Ignition system

Fuel injector circuit

ECM power source circuit

Mass air flow meter

Variable valve timing (VVT) system

Throttle body

Intake system

PCV valve and hose

Compression

No. 1 valve rocker arm sub-assembly*

Engine stalls only during A/C operation

A/C signal circuit

ECM

Unable/difficult to refuel

Fuel system (canister, refueling valve, roll over valve, fuel tank etc.)

-

HINT:

*: Check the "Fuel Cut Elps Time" in the Data List.

If the elapsed time is over 0 sec, then the engine speed is high (More than the engine speed at which fuel cut occurs + 500 rpm).

When this has happened, there is the possibility that the valve rocker arm will become loose and malfunction, so check that the No. 1 valve rocker arm sub-assembly is properly attached (See page ).

Test yourself

A quick Toyota Venza quiz: every answer comes with an explanation and a link to the manual page.