1991 Camry 2VZ-FE Engine; CO Emission Failure

Possible closure to this saga ---

Today I was told that yet another O2 sensor had arrived at te dealershhip. Vehicle has had a third O2 sensor installed that makes it "good to go" pass the NYState emissions inspection.

Yeah, 3 tries: First O2 sensor replacement on last FRIday Second O2 sensor on WEDnesday Third O2 sensor on THURSday, today

I have the original (I think) O2 sensor now in hand.

While viewing from the pin-side, the plug looks sorta like this:

___XXXX__ | | | [1] [2] | | | | [3] [4] | | | |__________ |

Where XXXX identifies the location of the plug's latch. The numbering shown above is for reference only. If the correct info is known, please provide it.

1= BLUE 2= WHITE 3= BLACK 4= BLACK

The CHECK ENGINE light is Out, so far.

The NYState emission test results at 63749 mileage are as follows: HC= 0.02 CO= 0.0 NOx= 0.41

I will be expecting an improvement in MPG !

Can anybody tell me the pin layout wiring /signal name and which colored wires should be used to test measure this O2's resistance ?

I supsect that the two BLACK conductors are used for a chassis ground connection.

The TOYOTA part number is: 89465-29285.

TNX. I am tempted to bring the vehicle to another inspecton station for reinspection, just to be certain ! ~ Vince ~