neoney

I’ve bought my first RX-8, and it has a P0130 code, which I’m pretty sure is related to the upstream / pre-cat O2 sensor. Before I go on about buying a new one, I’d like to test the one that’s in the car. Is there any method of doing that?

I’ve got access to a multimeter, which from my research I could use for that purpose. I thought I could unplug the O2 sensor under the hood, next to the oil filter, but I’m pretty sure if I did that I wouldn’t be able to reach to it with the multimeter anyways.

Any tips for testing it? Thanks.

Loki

iTrader: (1)

The code is being set because the sensor is failing the ECU's own testing, it's pretty conclusive. Thing about testing it on a bench is it needs to be heated to exhaust temperature, so you need to run 12v to its heater and all you'll really be able to confirm is continuity since it's in oxygen. Being a wideband, it's impedance based, not voltage based signal, so you'll also need to recreate the voltage the ECU puts on the signal line... honestly, I'd just replace it

neoney

Alright, I guess that’s what I gotta do then. Just didn’t want to spend all that money for it to turn out that the cable is broken somewhere or something like that.

As for the replacing, is the plug reachable at all do you think, or will I have to remove the intake manifold?

Also, I’ve heard people say the Denso sensor is a good replacement. I’ve got a '04 manual, so that would be the DENSO N3H3188G1A I think. Am I correct?

Loki

iTrader: (1)

You might have to remove the UIM but it's really not that bad. That sensor sounds right, it has a Mazda part number

neoney

Sensor replaced, codes gone. I was running a Delphi sensor I think, Denso DOX-1449 works fine. Shaky idle gone.
Managed to do it without removing the UIM, was tough but i couldn’t bother.