I rented the O2 socket set from autozone and tried to go at it yesterday. The most forward O2 sensor has room around it, but no where near enough to get the socket and a wrench in to get it off. the other front O2 has enough room for me to get the wrench and socket on the sensor, but then I have almost zero room to more twist the wrench. Lastly, this is a stupid question, but i just want to make sure. which way do turn the O2 sensors to get them off. looking at the threads of the new one's suggest counter clockwise just like darn near everything with threads, but i just wanna make sure. thanks

maybe taking off the y-pipe would help, I don't know though but I will be facing the same problem in a month, if nothing ****s up with money.

i was thinking about doing that but was worried about ripping seals or something. do i have to worry about anything when taking that off or is as easy as taking off the bolts?

I havent actually done this yet on the Maxima, but on the Jetta I used to have, I was in the same situation and I just hooked up a swivel joint to the socket and it worked pretty good. You might have a hard time with corrosion and if the previous replacement didn't have anti-sieze on it. Also, soak it with some PB Blaster or WD-40 or some lubricant for like 15 minutes before (while exhaust is cold)

Instead of the socket, try a 7/8-inch open ended wrench. They're usually long enough to get enough torque to remove the sensors.

The thread the same way as any other normal bolt. Turn it left to get it out.

haha, i had no problem doing all three of my 02 sensors i used a socket wrench

yeah, i spray wd40 and rust eater on it last night and let it sit since then. hopefulyl they'll come off easier when i try today.

I had the same problem. I could get the socket onto the sensor closet to the radiator, but there was no way to get a wrench connected to it. I ended up using a 22mm open ended wrench instead. It's a lot slimmer, and will fit. I don't even use the o2 socket anymore. Turn counterclockwise.

So why'd you guys decide to replace the O2 sensors? Is that a routine thing, or is there and engine light, or do you wait til bad gas mileage, or what? Thanks

that's what i did.

bad O2s causes bad mileage because it'll mess up your air/fuel ratio, therefore performance goes down. usually your CEL (check engine light) will tell you about an unfunctional O2 when it's bad.

anyone know which wrench it is for sure? 7/8-inch or 22mm? I'ma guess the 22mm but just want to make sure when i go to buy it. thanks

22mm. o2 sensor sockets are also 22 mm.

22mm wrench did the trick, took no more then 2 mins to get bougth 02 sensors loose. when i first put the new ones, they weren't tight enough and were leaking exhaust fumes. tightened up a lil bit more and i'm good to go. thanks

Yeah, a lot simpler and more convenient than using an o2 socket, isn't it? Works better, costs less. I wonder why people reccomend using the o2 socket at all. It's not easier or safer for the oxygen sensor. I snapped one sensor in half using the socket. With the wrench, the tool doesn't contact the wires of the o2 sensor at all, versus the socket where the wires can get twisted around the socket.

when i was in advanced autoparts, the guy there told me not to use a regular wrench because the 02 sensors are made of brass and the wrench would break it.The O2 sockets are made of some diff metal. He then showed me the 02 socket but then i went on to say i already have it and it doesn't work. didn't matter anyway since the largest wrench they sold was only 19mm. Napa autoparts is where I ended up buying it, it was only $4.59 after tax. was planning on buying then returning after I was finished with it, but at <$5.00, i'll keep it.

Different metal? So the socket metal is soft so it would bend before it could break the sensor? How does the wrench break the sensor? You're only applying torque to that big nut thing, not to the rest of the sensor, so the worst case I could see is that you'd strip the hexagonal nut, because brass is a lot softer than steel.

same thing i thought, thats why i went ahead and used the 22mm.