Can anyone tell me if the connectors on the 3.4L fuel ratio sensor (upstream) and the (downstream) O2 Sensor are the same or different? I'm having trouble identifying which is which. Perhaps there is some other way to tell them apart? They are both Denso and have numbers on them, but the numbers do not bring up relevant hits in a Google search.

BTW: My Taco is Non-California

Thanks!

 

Have you looked at Denso Aftermarket to figure things out??

If you list your year and drive train 3.4 Auto or manual federal spec it is easy to figure out

 

Yes, I've looked at that site. They list Denso part numbers, but they do not match the numbers on the O2 Sensors I have. I have them, because I swapped them out before, when I don't think I needed to. I believe they are still good, but I am not sure which is which now. One didn't seem to want to fit the female end of the connector for the downstream sensor. I was hoping someone might confirm (or deny) that the plugs are different to prevent mixing them up.

 

Do they have Toyota Part numbers ?

Looking at 97 and 2000 the plugs are the same

At least when the harness was new.

One finds all kinds of strange things done to electrical harnesses