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Oxygen sensor replacement

I was trying to replace the o2 sensor in my galant. However, I couldn't remove the old one from the exhaust. It's too deep to reach and I have no idea what kind of tool should I use. Any suggestions?
 

A crows foot or an oxygen sensor tool (similar to a crows foot but with a deeper socket type look). Oh and make sure you use some penetrant first to loosen it up some to make it easier to remove.
 

Dan D

Well-known member
Joined
Feb 27, 2001
Messages
1,171
Location
Brownsburg, IN
quote: It's too deep to reach and I have no idea what kind of tool should I use. Any suggestions? An extension?
 

4orced4door

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Jul 19, 2002
Messages
9,846
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Raleigh, NC
Even with the right tool mine rounded off. Doh! Now I'm waiting for my new o2 housing from Andy so I can replace the whole mess.
 

I am trying to replace my oxygen sensor right now what a pain in the ass. I have used penetrant the o2 deep socket and a nice 12 inch extention. Still no luck.

When you buy the o2 socket see if you can find a 22mm one. The one I have is a POS universal 7/8" and 22mm socket. The problem is that 7/8" is equivalent to 22.225mm not 22mm, so it has begun to strip the bolt corners. You may want to cut the wires and use an exact 22mm six point deep socket to get the old one out. Twelve point sockets suck. That is what I am going to try tommorrow.
 

Matt W

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Aug 18, 2001
Messages
382
Location
Noblesville, Indiana
It also helps sometimes to have the car warmed up.

PB blaster is also my choice of lubricants. Much better IMO than WD-40.
 

ken inn

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Feb 23, 2001
Messages
7,529
Location
krum texas
GTFFT! cost is about 30 bucks, fits perfect, pops that sucker right off. dont use the universal kd tools slotted sensor crap, it MUST be a closed 6 point. like he said, the only other option is to cut the wire, and use a deep socket, like an impact, and a huge breaker bar. dont forget to never sieze the crap out of the new one, it will have some on it, but more is ok. and use NICKEL based, all others will act like a threadLOCKER.
 

Hertz

Staff member
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Jul 29, 2002
Messages
13,501
Location
Chicago, IL
Took me about 2 months to get mine off, and I had to get Ken (Hibern8) to actually bust it loose.
smile.gif
I supplied him with a 5 foot length of pipe as a bar, seemed to do the trick.

About 12 applications of WD-40, dozens of muscle-straining attempts (without enough leverage) didn't do it. Leverage makes the biggest difference, and I would agree, WD-40 is not as effective as PB Blaster or Liquid Wrench, but it is better than nothing.
 

I had to actually stand inside the engine bay with my foot on the breaker bar .After a few buckets of cuss it finally snapped.I broke 2 extensions with this method.It was the biggest f*** job Ive had to do so far


Cruce
 

ken inn

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Feb 23, 2001
Messages
7,529
Location
krum texas
i just now took mine off. factory tool, 27mm box wrench, one yank, and i got it. hope the downpipe goes on as easy.
 

I just changed my O2 sensor about a week ago. I started to round it off cause it was so tight so I tool some MAF gas and toasted the sh*t out of it. I waited till it was cherry red and through the O2 Socket on it. The thing spun right off.

**Fire it up baby**

Alex.
 

gtluke

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Joined
Sep 16, 2001
Messages
4,210
Location
dirty jersey
ha wd-40 is garbage.
i use this stuff called "lube job" (ha right?)
it works incredible, and the cans last FOREVER. it sprays nice too... and its cheap. some woman just calls me at my work and asks how much more i need, otherwise i'd tell you guys how to get it
smile.gif

i think i've been though less than a case of it (12 cans) in about 3 years. i'm telling you these cans last forever. and i'm a professional mechanic
 

4orced4door

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Jul 19, 2002
Messages
9,846
Location
Raleigh, NC
Or you can do it the easy way and put a new o2 sensor in a new o2 housing.
wink.gif
 

broke down

Well-known member
Joined
Jul 15, 2002
Messages
1,075
Location
Muncie, Indiana
IMO, PB blaster is the ONLY rust penetrant to use soak it every day for a while. Also, try heat. A propane or MAPP gas cylinder should help. MAPP gas gets way hotter than propane, and since the o2 housing and sensor are used to extreme heat, they shouldn't get damaged from the heat. Get it red hot, then try.
 

ok i got my o2 sensor off no problem but the little f%^*er wont bite on the o2 housing. help. i have to go to work in an hour
 

If you are removing a bad o2 sensor you can just break it so you can get a socket on it. Use a 6-point socket to avoid rounding. Presoaking with deep creep or PB Blaster helps.

I replaced mine when I changed the O2 housing. The problem wasn't a bad sensor. But the thread lands were messed up so that the sensor wouldn't seat into the new housing. I probably could have gotten it on eventually but I didn't want to mess up the threads on the housing in the process.

BiggiB42... this may be the problem you are having. Check the condition of the threads on the sensor and on the housing.
 

i managed to get the sensor on i just was having trouble with the angle i was putting it in
 

quote:Originally posted by ken inn:
i just now took mine off. factory tool, 27mm box wrench, one yank, and i got it. hope the downpipe goes on as easy. Do you have the part number for the factory tool?
 

Also, where can I check the o2 sensor heater ground (I think that's what it is called)? I tried removing the sensor today with no success, but I plan on using another o2 socket soon. Any help is appreciated.
 
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