Help Sensor Question

[Kryz]

Are any of the o2 sensors on the Lexus Mk1 wideband? i.e. give a signal between 0volts and 5 volts?

I beleive they are all narrow (between 0 volts and 1 volt) however just wanted to make sure.

I have an GS300 MK1 SE. I know toyota put some wideband sensors on some cars in 1997.

Anyone help out there??

[BigRoj]

Just checked the manual and according to that if it reads 0v its knackered, at 5v its lean, so from that you can deduce they are wideband, ie0-5v.

Probably.

[Kryz]

Just checked the manual and according to that if it reads 0v its knackered, at 5v its lean, so from that you can deduce they are wideband, ie0-5v.

Probably.

Is that for the MK1 GS300?

[Kryz]

Just checked the manual and according to that if it reads 0v its knackered, at 5v its lean, so from that you can deduce they are wideband, ie0-5v.

Probably.

Is that for the MK1 GS300?

DTC 21, 28 Main Heated Oxygen Sensor Circuit

CIRCUIT DESCRIPTION

To obtain a high purification rate for the CO, HC and NOx components of the exhaust gas, a three way cata-

lytic converter is used, but for the most efficient use of the three way catalytic converter, the air–fuel ration

must be precisely controlled so that it is always close to the stoichometric air–fuel ratio.

The oxygen sensor has the characteristic whereby its output voltage changes suddenly in the vicinity of

the stoichometric 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 ECM 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 is reduced and the oxygen sensor informs the ECM of the RICH condition (large electromotive

force: 1 V).

The ECM 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 an

output of abnormal electromotive force, the ECM 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 con-

trolled by the ECM. When the intake air volume is low (the temperature of the exhaust gas is low) current

flows to the heater to heat the sensor for accurate oxygen concentration detection.)

From the manual for the MK1.

Looks like its a narrow band

[BigRoj]

Oh! The info I got was from a diagnosis chart from the mk1 GS w/shop manual. Confusing!!!