9 replies to this topic

[Avl_Paul]

So, I believe my O2 sensor was damaged recently when I had a welding shop install a new exhaust on my 95 SPI Mini Cooper.   Rather than spend a lot of time troubleshooting, I decided to just go ahead and replace it (big mistake - I should have done the troubleshooting).  I removed the throttle body and intake manifold and used a 22mm O2 sensor socket (while heating the bung with a torch) and applied a breaker bar.  Unfortunately, the hex on the O2 sensor started to round (and the socket turned) before it came loose.  I can still get some bite with the socket and have been trying additional heat and PB Blaster to loosen things up but with no success.  I also tried using an impact wrench.  Still no luck.

 

Any advice?  How do I get this out?  If I round it completely, do I have to pull the whole exhaust manifold and exhaust off to take it to a machine shop?   Should I put it back together and take it to a mechanic before I do any more damage?

 

 

[firstforward]

I have not used an O2 Sensor socket, are these the type with a slit down one side to allow the cable to clear the socket? if so is that allowing the socket to expand and lose grip? again if so, cut the wire so the connector is removed that will allow a proper long reach socket that will fit better and not expand and lose grip.  You should not need to use any heat.

 

Edit: This all depends on how much you have mullered the Hex already, in the unlikely event you cannot remove it, best to take the complete manifold off.

Edited by firstforward, 27 July 2014 - 08:48 AM.

[dbcool20]

i know this doesn't help much to remove the sensor, but when installing the new one put a little bit of high temp or copper grease on the thread of the sensor. like this it will make it much easier to remove for the next time and won't seize up. 

[Fossy313]

if i was you, cut your losses get the manifold off, stick it in a vice and the leaverage should be enough to get the sensor off, either way if its still on the car you dont know what damage your doing to it, if i was ever going to get the o2 sensor off id be taking the manifold off, realistically its a half hour job to get the manifold off.

 

be careful using heat.....its a sensor afterall (granted that built to withstand alot of heat but still,

[Avl_Paul]

Is it really only a half-hour job to get the manifold off?  well, ****, I thought way longer.  I've spent multiple hours trying to get the O2 sensor out.    Don't you have to get under the car and unbolt the down pipe?   (Car is stored in my  ex-wife's garage so I can't look at it right now.)   

 

Frustrating this is that I DID use anti-sieze and it only has like 1000 miles on it since last changed.  Can't understand why it is so stuck.   I was going to try an air-powered impact tomorrow and, if that didn't work, put it back together to take to a shop (but hard to find anyone to work on Classic Mini SPI here in States).   I'll  go after removing the Exhaust manifold next.  Will I need a new gasket (is there a gasket)?

[andyteethyea]

Mine was stuck solid the lambda sockets i have are like impact sockets so nice and strong but i have a strong arm and i had to bounce it with my whole body waight slowly not to snap anythink to get the sensor out it was a huge and scary pain in the bum

[andyteethyea]

Btdubs my manifold was still on the car

[FlyingScot]

I have never had much success with the expensive sensor socket, I bought. I ended up cutting the cable off (part through the crimped bit and ceramic) then proper socket and solid bar. Bounced it a couple of times then bang and it undid.

FS

[Fossy313]

there is still so many wires (if we are talking about an mpi) that you can get caught on etc etc, yep half hour job for the manifold easy,

 

unplug fuel feeds, unclip the injectors, map sesor IAC sensor, few others, air filter off, downpipe off (but u can get under with axle stands and wiggle it out with some anti sieve stuff,

 

4 boths for manifold to inlet.....off it comes,

 

in vice, bam off it is, with no damage.

[brivinci]

I just did this on my SPI...WHAT A PAIN IN THE ASS!!!! I have a Maniflow LCB and I could not get it apart at the bottom "Y" so I worked with the header in the car. Wow it totally sucked. If you can get the mani out, do it that way. That is the way I got it out the first time. Also, if you dont heat, I'd say your out of luck. I had to get mine cherry red in order for it even budge. By the end, the lambda was totally toast. It was in many many piece and the threads ended up ripping off and stayed inside the header. I was able to remove and reuse it the first time though. The car had 40k on it and with heat, it came out of the stock exhaust manifold in a useable state. I used the special socket. They are not expensive here but I bet the more expensive ones are better quality/tolerances. VERY easy to strip these. Oh, I also removed my head to gain enough access as I was replacing the head.

 

Long story short, remove the manifold and if you have to, take it to a muffler shop and have them remove it with all the correct stuff.

 

Sorry, just saw that you are in the States as well. Where abouts? IF you need help with stuff, please feel free to give me a shout. I've done just about every terrible, painful job on these cars:-)

Edited by brivinci, 31 July 2014 - 06:15 PM.