So..... The rear O2 sensor wire was missing on my '97 OBS -- chewed right off of the sensor, and the harness is missing (it sits on the transmission, and I think it went with the old transmission when the dual range transmission was installed...). I got a used harness and sensor from superrupair, but now, up by the engine, I've got two male plugs -- one on the engine harness and one from the harness going over the transmission.... not going to plug into each other . And the wire colors aren't the same on both sides either, or I'd just splice it and take the plugs off. Did subaru use different plugs for different years/cars that might not all be the same, for the rear O2 sensor? The plug for the rear O2 sensor IS right next to the one for the front sensor, right? Or wrong?

 

Also... do I even care? It's getting lousy mileage (24mpg) but that's probably the front sensor, from what I've read, and I do have a new one for that. And I having the check engine light on does not cause it to fail emissions in of itself here. So... if the rear is not doing anything, maybe I should just replace the front one and call it good?

 

On a good note, the low range is awesome... I took it down a pretty gnarly trail, and it could use a bit more clearance (forester struts coming...), but it sure can climb hills nice.

 

Thanks

I would recommend getting the rear sensor working and tied into the ECU.

 

I do not believe the wiring for the front and rear sensor are next to each other. I'd have to follow the wiring of the rear sensor to see, but I'm pretty sure it ties in at a different spot.

 

This may help...

http://www.main.experiencetherave.com/subaru_manual_scans/FSM_Scans/1997_Impreza_FSM.zip