I have 95 legacy, 76K miles, the check engine light goes on and off randomly. I'm thinking O2 sensor, and since I dont have time to go to the dealer to get codes read, and the sensor could use a change, I want to replace it. How many are there? Where can I find one that is basically OEM and not a peice of junk replacement? Thanks.

You could try an autozone or someplace like that for free code reading. Yes you have a '95 but lots of '95 Suby's ODBII compliant maybe with a glitch or two.

 

There should be one front and one rear o2 sensor. Generally you would replace the front one first and if still getting P0420 then replace rear. Front is for air fuel ratio control in closed loop; rear is simply for 'catalyst efficiency.'

 

Where can I find one that is basically OEM and not a peice of junk replacement?

That's an easy one. From an online Subaru dealer such as http://www.subarugenuineparts.com or http://www.subarupartsforyou.com

There have been a few extensive O2 sensor threads here. Do a search and I'm sure you'll pick one up.

 

The 1995 Legacy has a technical service bulletin for O2 sensors "freezing up" in cold weather. I found out the hard way after replacing a $few$ on my 95 to no effect. I now just ignore the intermittent CEL in really cold weather. My mileage takes a slight hit but it's no where near the cost of an O2 replacement. However, if gas keeps going up...