Advertisement
CLICK HERE TO VIEW CHAPTER INDEX
DTC
CIRCUIT DESCRIPTION
To obtain a high purification rate for the CO, HC and NOx components of the exhaust gas, a three--way
catalytic converter is used, but for the most efficient use of the three--way catalytic converter, the air--fuel
ratio must be precisely controlled so that it is always close to the stoichiometric air--fuel ratio.
The oxygen sensor has the characteristic where by its output voltage changes suddenly in the vicinity of the
stoichiometric air--fuel ratio. This characteristic is used to detect the oxygen concentration in the exhaust
gas and provide feedback to the computer for control of the air--fuel ratio.
When the air--fuel ratio becomes LEAN, the oxygen concentration in the exhaust increases and the oxygen
sensor informs the engine ECU of the LEAN condition (small electromotive force: 0 V).
When the air--fuel ratio is RICHER than the stoichiometric air--fuel ratio the oxygen concentration in the ex-
haust gas in reduced and the oxygen sensor informs the engine ECU of the RICH condition (large electromo-
tive force: 1V). The engine ECU judges by the electromotive force from the oxygen sensor whether the air--
fuel ratio is RICH or LEAN and controls the injection time accordingly. However, if malfunction of the oxygen
sensor causes output of abnormal electromotive force, the engine ECU is unable to perform accurate air--
fuel ratio control.
The main heated oxygen sensors include a heater which heats the zirconia element. The heater is controlled
by the engine ECU. When the intake air volume is low (the temp. of the exhaust gas is low) current flows
to the heater to heat the sensor for accurate oxygen concentration detection.
P21242 FI7210
DTC No.
At normal driving speed below 100km/h (60 mph) and engine
speed is above 1,500 rpm amplitude of oxygen sensor signal
P0130/21, 28
is reduced to between 0.35 - - 0.70 V continuosly for 60 sec. or
more.(2 trip detection logic)
DIAGNOSTICS
P0130/21, 28
Atmosphere
Cover
Exhaust Gas
DTC Detecting Condition
- -
ENGINE (2RZ- -FE, 3RZ- -FE)
Heated Oxygen Sensor Circuit Mal-
function (Bank 1 Sensor 1) (2RZ- -FE).
Flange
Platinum Electrode
Solid Electrolyte
(Zirconia Element)
Platinum Electrode
Heater
Coating (Ceramic)
S Open or short in heated oxygen sensor circuit
S Heated oxygen sensor
S Engine ECU
3RZ-F,3RZ-FE
Pages From Supplement
TO MODEL INDEX
Ideal Air--Fuel Mixture
Richer -- Air Fuel Ratio -- Leaner
Trouble Area
CONTINUED
DI- -119
DI1IF- -01
A00027
Hide quick links:
Advertisement
Need help?
Do you have a question about the 1RZ and is the answer not in the manual?
Questions and answers
1rz engine can't pick up fast and sounds as if not enough fuel reaching the engine
A Toyota 1RZ engine with slow acceleration and symptoms of insufficient fuel may have issues related to the fuel injection system, ignition system, or air intake. Possible causes include:
1. Fuel Injection Issues – Clogged or malfunctioning fuel injectors can reduce the amount of fuel delivered to the engine, leading to poor acceleration.
2. Fuel Pressure Problems – A weak or failing fuel pump, clogged fuel filter, or faulty fuel pressure regulator can restrict fuel flow.
3. Ignition System Faults – A weak spark due to worn spark plugs, faulty ignition coils, or incorrect ignition timing can affect combustion efficiency.
4. Airflow Restrictions – A dirty or clogged air filter or a malfunctioning throttle body can limit the amount of air entering the engine.
5. Sensor Malfunctions – A faulty mass airflow sensor (MAF), throttle position sensor (TPS), or engine coolant temperature sensor can send incorrect signals to the ECU, affecting fuel delivery and timing.
6. Starter Signal Circuit Issues – If the starter signal is not properly received by the ECU, it may affect the fuel injection control, leading to poor performance.
7. Knock Sensor Issues – A malfunctioning knock sensor or related wiring problems could cause the ECU to retard ignition timing, reducing power.
A proper diagnostic check using an electrical tester and oscilloscope can help identify the exact fault.
This answer is automatically generated
Engine not having full combustion, loss of power and blackening plugs
A Toyota engine with part number 1RZ experiencing incomplete combustion, loss of power, and blackened spark plugs could be caused by the following issues:
1. Ignition Problems – Faulty ignition coil, igniter, or spark plugs can lead to weak or no spark, causing incomplete combustion. (Referenced in DI--151, IG--1)
2. Injector Circuit Malfunction – A faulty injector or injector circuit may cause excessive fuel delivery, leading to rich fuel mixture and blackened spark plugs. (Referenced in DI--158)
3. Airflow Meter Circuit Issues – A malfunctioning airflow meter can provide incorrect air intake readings, leading to an improper air-fuel mixture. (Referenced in DI--94)
4. Fuel Pump Control Circuit Fault – A malfunction here can result in incorrect fuel pressure, affecting combustion efficiency. (Referenced in DI--174)
5. Variable Resistor Circuit Malfunction – If applicable, this can affect sensor inputs to the ECU, leading to improper fuel delivery. (Referenced in DI--183)
6. Engine ECU Malfunction – A faulty ECU can cause incorrect fuel injection timing and mixture. (Referenced in DI--170)
These issues can lead to an overly rich fuel mixture, causing blackened spark plugs, reduced power, and inefficient combustion.
This answer is automatically generated
Location of the fog fuse relay on the box