chriscross

I tested my O2 sensor, using the method on Clark's garage, and the voltage is not climbing when rich. The exhaust also smells like fuel - a lot (with or without the O2 connected). So, I bought the universal Bosch sensor (that splices in), but I cannot get the old sensor off. I have spent two days spraying a can of PB blaster on it and it will not budge - I have tried torquing it off using a big a$$ breaker and my foot, but I am at the point of rounding the edges off the bolt and by "at the point" I mean I have rounded off some of the bolt.

I have seen that some people recommend using a torch, until it is cherry red, but I only have jack stands and don't feel comfortable/trust myself to squeeze under my 944 and torch it, without burning myself, the car and possibly the entire garage I rent and the owner's house

Are there any other tricks for getting this out?

FYI, the reason for all of this is that I have until July 13th to pass DC emissions and I think this is the last piece in the emissions testing puzzle. I already replaced the AFR - there was fuel in the vacuum line. Also, when I bought the car a of couple months ago I did the distributor cap and rotor, new wires, new plugs, oil change and recently replaced the belts. I also set the FQS to 6 on my last visit.

Just in case this helps here are the values from my last visit:

HC was 2.4 gpm with a legal limit of 2.0
NOx was 3.4 gpm with a legal limit of 3.0.

My CO was well within bounds (I forget what this reading was and the paperwork is with the car). Those values are after replacing the AFR and setting the FQS to 6 (retard timing and lean out fuel). The initial values were HC 2.8 rpm and NOx 3.8 gpm. I also have a gallon or two of Xylene as a last resort. Everything in the engine is bone stock and I am running a stock DME chip.

I appreciate any help. Thanks!

Grandpa#3

Hi Chris, The o2 Sensor can be a B***h to get off. Now that you have rounded off the nut you will have to use large vise grips or a small pipe wrench. Heat from a Propane Torch will loosen the Sensor enough to remove it. If you are afraid of a fire get a buddy to stand-by with a fire extinguisher. Tie a string to the sensor to be able to pull back the wire to the exhaust. The below post is what I found on SEARCH.

https://rennlist.com/forums/944-turb...Sensor+removal

Cheers,
Larry

drwhosc

I feel your pain, just went through this. I could not get this off for anything. I dropped the exhaust, and tried to get a better angle on it, still would not budge. Fianlly, I broke off the old O2 sensor, and had to drill and re tap. Not a big deal, the tap is a standard sparkplug size. Fairly available and fairly inexpensive. also if you have to go this route, get the drill bit that goes with the tap.

People say heat has to be applied. I tried to heat mine, but it was really really stuck, Hopefully you are not as extreame as me, but if you are, not a big deal really.

Also dropping the exhaust is not that big of a deal...

StoogeMoe

I was always successful at getting them out by going for a nice drive. As soon as you get home, have the wrench ready. That way you don't have to apply external heat from a torch. You just have to be careful around all the hot exhaust.

chriscross

Larry: Thanks, for the info on the vice grips. I saw the string idea in another post and have used it already - ingenious. It looks like a torch might be the only way.

drwhosc: I think you may be on to something about dropping the exhaust. I was contemplating that when I was under the car yesterday and you have now confirmed. I hope those exhaust bolts budge easier than the O2 =) I would also feel better about torching it, if was off of the car. Thanks!

chriscross

StoogeMoe: That is the easy way that I was looking for - thanks. Time to go for a drive.

Maybe I should take a drive to HD and get a torch just in case...

bordin34

Thats the way I did it. Mine was stuck and started stripping so I took it for a drive and it came out easily.

chriscross

So, I've taken it for a drive and also torched the heck out of the bung until everything was cherry red and it still won't budge. I am just taking chunks outs of the O2 at this point. I also can't get the midpipe out, because the nuts at the Y are one rusty lump of metel, with no resemblance of a bolt pattern.

Does anyone know of a good, reasonably priced shop around DC? Is this something a decent muffler place can do?

...Or does anyone have the tools at home and would be willing to help for a small fee/case of fine beer? =)

Thanks. I am going to go pass out from heat exhaustion now. It's only 102 F here.