Stupid O2 Sensor on the Mazda

[Rileysowner]

I finally got a code reader and checked the codes on my wife's Protege. It turns out what we triggering the check engine light was the second O2 sensor. After a little shopping and finding out the out of this world price for that second sensor, I asked my BIL if he could get me one through his autoservice place. Saved me $65 off the best price I could find.

However, today I tried to get the old sensor out. It won't budge. Not at all. Any suggestions on how I can get it out (or even moving )

[CaptSquid]

A small shaped charge? A small thermo-nuclear device?

Are you using the specialized socket or a flare wrench to get it moving? How about a generous application of weasel pi$$?

[Rileysowner]

I have an O2 socket, but it really is no help in getting it out. I have soaked it in Release All, but after an hour of fighting with it, plus the 20 minutes or so I let it soak to start with, I decided that it will simply have to wait until another day. However, we are heading out on vacation (not taking the car) and I would like the job done before I go so it isn't waiting for me when I come home.

[kings-x59]

Rather than trying to muscle the wrench, you might try hitting the end of the wrench with a rubber mallet.
I do this all the time. It has saved me many a busted knuckle.

[SoCalli V8]

Penetrating oil and the correct sized wrench + patience

[Rileysowner]

Thanks everyone. I have been soaking it in penetrating oil and will continue to do so today. I'm pretty sure I have the correct size wrench as it fits tight, so it is just a matter of getting some patience. I will update on how it goes.

[astrozam]

Sometimes the only thing that will work is a little heat.

[Jim in Indy]

You can prolly than the last person who replaced it for NOT putting a little anti-sieze on the threads....

Soak the heck out of it with PB Blaster, (or equiv), then wrap it in a shop cloth, then with plastic, then fill that thing with your liquid break free stuff & let it soak. The reason for the shop cloth & plastic it to keep the thing sopping wet to give a better chance of the rust-buster to work.

If you apply heat from a torch, or by starting the car, be careful as most rust-buster liquids are flammable, and at the least they give off nasty fumes when heated/burnt.

A long pipe on the end of a wrench (3' chunk of iron pipe) can always be an aid.

[CaptSquid]

Those solutions aren't nearly as spectacular as a small thermo-nuclear device.

[kings-x59]

very true squiddy, however, he'll have a van left when he does get it out.
maybe his house too.....

[reaper]

Sometimes the only thing that will work is a little heat.

X2
I went thru this with Steph's van,The 02 would not budge.
So I fired it up,went for a drive,got the exhaust hot,went underneath
& loosened it out.

[Kidhauler]

If you have air tools and can get a impact gun on the sensor turn your air pressure down so the gun is just racheting and banging against the bolt the vibration should loosen it. Plus you can slowly turn up the air and put more power to the gun.

[Rileysowner]

Nope, no air tools. I have been working at convincing my wife I need a compressor, but so far with little success.

As to heat, any problem running without the second O2 sensor to get the exhaust warm. I have it disconnected and it is pretty much smashed from my attempts to get it out. Hey I wasn't too worried if it got damaged as I have to put in the new one. Not that I set out to damage it, it was one of those times when I was reaming on it and the wrench slipped.

[potskie]

for the cost of em nowadays a cordless electric impact is the more economical choice.


Did you try a socket/johnson bar?

I use a 6' peice of pipe on the end of a breaker handle to get those tough suckers even my impacts won't crack. The bar I use creates enough leverage that I have actually lifted the rear of the van off the ground while trying to crack a very rusted bolt.

There is also the ghetto impact trick. Take a socket / ratchet get them on there and smack the ratchet handle with a heavy mallet or dead blow hammer. Even a regular framing hammer works. just smack it off the handle repeatedly. make sure the handle doesn't bounce back to far tho or you loose some of the effect. I only recommend this method with lifetime warannty tools or crappy old one as it has been known to shatter the ratcheting mechanism.

[thevalleyboy]

Don`t use an impact gun on a o2 sensor - if you cannot remove it with a snipe (3`pipe) and some muscle you have bigger problems - seriously - take it easy and get that thing out - if you cannot take it to a shop - let them screw the car - at least it will bo on their tab to fix it - or it should be - tight is one thing - unmovable is a total other..... best of luck