I Installed It with my RB Header, last Summer.

I verified It wasn't working by, for one, poor gas mileage. My AF Gauge stayed on the first red light- Lean. I also plugged In a LED Lite In the Diagnostic Plug. One for the 12v and the other grounded Into the 02 Sensor diagnostic plug. There, you'lll get 8 flashes followed by a pause, repeat, awhile cruising. Also, I wasn't getting a direct voltage reading of the sensor Itself.

I had a Bosch O2 Sensor In there. The only explanation I have Is I may have running rich on premix (14oz/per fillup) and have zero emissions which may have caused premature failure. Anyone?

 

Running no or a bad o2 sensor makes you run stupid rich at idle/low rpms. Use a OEM mazda o2? have you tried cleaning off the o2 and reinstalling it?

 

The Bosch Is no different than the OEM one...except with the exeption of the Plug Itself. I Installed a Bosch once again. I've since started premixing at 12oz per/fillup. I did this too b'c I had discolouring on my s.s Tail pipes. Although, zero Cats contributed to this aswell.

 

But getting the code doesn't necessarily mean failure, correct? I imagine you've already checked the connection, cleaned the threads on the sensor and the manifold, and cleaned the sensor as Drox said?

Basically, are you sure it failed? Pre-mix shouldn't cause one to fail any faster than burning mineral based oil would, exspecially if you're running one with the TW-C3 rating.

 

Running rich will quickly kill the O2 sensor, which will make the car run richer...and the cycle continues. But are you sure the connection just isn't loose? The ECU doesn't really check the O2 sensor to see if it is out of value, only checks to see if it is there.

silverrotor is correct in that the standard Bosch sensor is fine for replacement.

 

I did check the connections, cleaned off the O2 Sensor with compressed air and a dry rag. I also checked the Engine Codes, although, as mentioned, won't always show. I believe I am running to damn rich.

Soon enough, I'll dyno tune my S-AFC. I've had It In for about 6 months now on default. Still modding 'til due date at the Dyno.