How difficult is it to replace Oxygen Sensors yourself? Is it a simple part replacement... are they tough to get to? Is it easy to pull the Y pipe to get to the front one?

Any thoughts would be helpful, thanks.

 

Taylor ('98 OB)

The only O2 sensor I ever replaced was on my friend's 92 Cherokee. That took all of 10 minutes. You'll need a O2 sensor removal tool, which is basically a 5/8 (that right?:eh: ) socket with about a third cut out so you don't damage the pigtail. Do it when the exhaust is cold. If it's hot, it will not only increase the risk of getting burned, but the expanded metal will make loosening it harder.

 

I understand your concern for the Y-pipe on Subarus, however, I would think if you drove the car up on ramps that it wouldn't be too hard.

I had mine changed just recently at the dealer and was surprised to see an hours time charged! I don't know what is truly involved and I'm pretty much past doing that sort of thing myself. The threads looked pretty torn up on the old sensor. These things can just about weld themselves in over time with the thermal cycling, exhaust gases, etc. It's a bit of a crap shoot as to whether you will have problems getting the old one out or not.

 

It has made a difference on my 97OB. My milage had slipped a little (say 3 to 5%) and that has come back. As well, the carbon build up issue (just posted in the other thread) was being aggrivated by a drifting (failing) O2 in my opinion. I never had a CEL though. I only changed the front O2.

 

Commuter

The dealer charged you an hour because, in my experience anything that involves turning a wrench incurs a minimum 1 hour labor charge.

I replace mine on a 97 Legacy.

Took me around an hour because the bolts on the shield on the exhaust pipe were rusted and welded to the shield because of the heat. I had to cut them off to remove the heat shield. I replaced the front O2 sensor. It seems that the rear sensor should not take more than 1/2 hour.

Once that was off, it took me around 20 mins to uncrew the O2 sensor, put another one in and put everything back together.

So far, no CEL!

Replaced mine on a 96 (2.2L).

Measure the new one to find a suitable open wrench . I dont remember the exact size.

Just bend over the right fender and go at it. No need to go under, put the car on ramps on remove the heat shield. It's just under the right side inner cv boot. It took me 5 min to remove it, 10 to splice in the new pigtail (i bought a cheaper universal one) and 5 more to screw the new one in.

I usually take more time than most people here to do a particular job. So it must be very easy.

Good luck!

No doubt, o2 sensor is easier than changin plugs on a 2.5 .

And put a little anti-seize grease on the threads for next time.

locktite has some really good anti-seize.