02 sensor issues!!! (Removal)

[Trstno1]

Well-

I tried pretty much everything to get the old O2 sensor out in order to replace it...(heating/penetrating oils/time/ breaker bars). Nothing has worked. Then, the last time I attempted to crank on it the O2 sensor finally broke free, but unfortunately left its threads in the crossover. Does this happen often to other folks? What has everyone done to fix this? Anything? I really don't have the coin to be purchasing a spec 1 exhaust right now......

1. Maybe put a torch to the bung and atempt to use an easy out?
2. Try purchasing a good crossover pipe with a good hole, then break other exhaust bolts getting it out?
3. Weld it closed, and have a new bung welded in ( which would require it to be out of the car )?
4. Try to get at it with a pick/chisel and hammer and break it out?

Help! :what_the:

[DMCMW Dave]

Well-

I tried pretty much everything to get the old O2 sensor out in order to replace it...(heating/penetrating oils/time/ breaker bars). Nothing has worked. Then, the last time I attempted to crank on it the O2 sensor finally broke free, but unfortunately left its threads in the crossover. Does this happen often to other folks? What has everyone done to fix this? Anything? I really don't have the coin to be purchasing a spec 1 exhaust right now......

1. Maybe put a torch to the bung and atempt to use an easy out?
2. Try purchasing a good crossover pipe with a good hole, then break other exhaust bolts getting it out?
3. Weld it closed, and have a new bung welded in ( which would require it to be out of the car )?
4. Try to get at it with a pick/chisel and hammer and break it out?

Help! :what_the:

It's kind of a mess any way you look at it.

Best bet - get a good used crossover (with all the aftermarket exhaust kits sold they are not hard to find and shouldn't cost much). Get the hardware (4 manifold studs, 8 nuts and washers). Then you still have to get 4 bolts off the converter and another 4 off the manifold flanges, which are also fun to get apart without breaking.

It's really going to be hard to extract that old one in place, but you may as well try because you don't have much to lose. I'd say try an ez out but only if you haven't been heating it all along. If heat didn't work before it broke, it probably won't work with an ez out either.

My guess is that you didn't get it hot enough. You need to get the bung bright red before you start cranking on the sensor.

[sdg3205]

My guess is that you didn't get it hot enough. You need to get the bung bright red before you start cranking on the sensor.


+1.

Probably my mistake too. Don't use propane. Get a hotter torch.

[dn010]

Any time my sensor wouldn't move I've always gotten away with running the engine up to temp prior to removal, but wear gloves!

[alexwolf1216]

Ive got a crossover I just pulled from my car. O2 came right out, PM me if interested.

[Trstno1]

Alright guys-

I soaked the area with PB blaster once a day for 4 days while waiting for tools to arrive. I ended up purchasing a MAP torch and an easy out set. I got the bung red hot and tapped in the easy out, but.....no go. All I could accomplished was shredding some of the metal from the broken O2 threads in the bung. I feel if I keep going the threads in the bung are going to be shot for sure. What a PITA area to be working - not a lot of room for much of anything.

I'm starting to think that taking the crossover pipe out is going to be my only option. But do I attempt this myself or limp it to a shop that has more experience with this sort of work? Im not even sure If it's even safe start the engine w/o the O2 sensor installed....I'm guessing not. Which unfortunately means a flatbed tow to a shop. However, if I could get the crossover out I could work on it out of the car and if it's screwed ultimately at least it's out for another one to go in. problem now, how to get the crossover out without breaking any bolts. Any suggestions? What tools are people using to get the proper torqe on the nuts holding on the crossover? Should the car be on a lift when attempting this sort of work? Currently, I just have the rear end up on jack stands. :dunno:

If I break bolts on either the CAT or the exhaust manifolds where the y pipe attach am I commited to a new exhaust system? Or can I purchase replacement studs for the CAT and exhaust manifolds? I'm starting to feel like this job has the potential of going downhill quickly. The absolute last thing I want to do is end up having to remove the heads for a trip to a machinist.

Dammit! After all........this all started with just wanting to replace the O2 sensor to see if it would help with my running rich issue. Easy enough right? :swear1:

I sure would appreciate any suggestions I can get from people who have removed their own exhaust systems, or have had this particular issue. What did you do?

[sdg3205]

Yup, recall my thread? When I started to remove the cat the bolts broke too. It's a risk.

If they aren't coming out when they're red hot I'm not sure what else can be done.


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[DMCMW Dave]

You can drive it with the O2 sensor out. It will be very noisy and the hot gasses coming out won't do things in the area much good, but a few miles should not hurt anything.

Someone who is good at heating all the nuts with a torch before even trying to loosen anything should be able to get the nuts off the crossover/manifolds/cat. They are all replaceable in-place although replacing the studs in the cat can be problematic as there is at least one of the studs that will not go into the cat flange from the back so would have to be replaced with hard-to-access nuts and bolts and may require some welding. If you run into that you'll want to remove the cat.

You should not have to remove the manifolds, but if you do you should have no reason to remove the heads, although drilling out broken head studs in place requires lots of dexterity, a right angle drill, and care to not drill through into the head. You will have this issue if you remove the manifold whether or not you replace everything, although I believe all of the aftermarket headers can use the opposite holes in the heads if needed.

It can be done without a lift. Depends on your dexterity and willingness to work on hot metal over your head while lying on your back.

If you have never done this sort of work before it's advisable to find someone who has. It's a bit of an art and people who only work on late model cars, or are lazy about rust work, won't get it.

[Josh]

you can drive without an 02 sensor, this is what we call open loop, lots of guys run their car permanently like this. Not saying it is a great idea at all. but for limping around it is not an issue.

It will be noisy as hell though as you now have a very significant exhaust leak lol.

I have a crossover pipe that is all your if you pay shipping. Let me know!

[Trstno1]

you can drive without an 02 sensor, this is what we call open loop, lots of guys run their car permanently like this. Not saying it is a great idea at all. but for limping around it is not an issue.

It will be noisy as hell though as you now have a very significant exhaust leak lol.

I have a crossover pipe that is all your if you pay shipping. Let me know!

Pm sent!

[Trstno1]

You can drive it with the O2 sensor out. It will be very noisy and the hot gasses coming out won't do things in the area much good, but a few miles should not hurt anything.

Someone who is good at heating all the nuts with a torch before even trying to loosen anything should be able to get the nuts off the crossover/manifolds/cat. They are all replaceable in-place although replacing the studs in the cat can be problematic as there is at least one of the studs that will not go into the cat flange from the back so would have to be replaced with hard-to-access nuts and bolts and may require some welding. If you run into that you'll want to remove the cat.

You should not have to remove the manifolds, but if you do you should have no reason to remove the heads, although drilling out broken head studs in place requires lots of dexterity, a right angle drill, and care to not drill through into the head. You will have this issue if you remove the manifold whether or not you replace everything, although I believe all of the aftermarket headers can use the opposite holes in the heads if needed.

It can be done without a lift. Depends on your dexterity and willingness to work on hot metal over your head while lying on your back.

If you have never done this sort of work before it's advisable to find someone who has. It's a bit of an art and people who only work on late model cars, or are lazy about rust work, won't get it.

I'll try getting the crossover out myself first. Quick question though..... When using the torch, should I be heating the nut or stud? I'm guessing you would want the nut to expand with heat right?

[Trstno1]

Yup, recall my thread? When I started to remove the cat the bolts broke too. It's a risk.

If they aren't coming out when they're red hot I'm not sure what else can be done.


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Oh yeah, I remember your thread for sure. I keep checking it to see if there are any updates.

[Trstno1]

Well.....heated up one of the four nuts holding on the cat till it was glowing red.....applied minimal pressure and....snapped bolt :swear1:

Now that I know this is the way it's going to go I'm worried about the manifold studs that hold onto the crossover going the same way.....not good..... :nervous:

[DMCMW Dave]

I'll try getting the crossover out myself first. Quick question though..... When using the torch, should I be heating the nut or stud? I'm guessing you would want the nut to expand with heat right?

Yes, the nut, bright red, but not all the way to white (melting point). Sometimes heating/cooling a couple times is good. Sometimes they will break anyway. Rust is a b**ch.

[Trstno1]

Alright.....update!

Every friggin bolt snapped except one. I have reserved myself to the fact that I an just going to update the whole system. I took everything out just short of the exhaust manifolds themselves. Now, I'm going to use oil penetrating on the manifold bolts everyday for about a week, but I'm guessing they will probably end up the same as all the others.

Is it correct to say that all aftermarket headers use the opposite holes in the engine to mount?

[alexwolf1216]

Alright.....update!

Every friggin bolt snapped except one. I have reserved myself to the fact that I an just going to update the whole system. I took everything out just short of the exhaust manifolds themselves. Now, I'm going to use oil penetrating on the manifold bolts everyday for about a week, but I'm guessing they will probably end up the same as all the others.

Is it correct to say that all aftermarket headers use the opposite holes in the engine to mount?

I used the freeze stuff for the manifold bolts and it worked beautifully.

[Trstno1]

I used the freeze stuff for the manifold bolts and it worked beautifully.

Freeze stuff? Do tell.....

[alexwolf1216]

CRC Freeze-Off Super Penetrant https://www.amazon.com/dp/B000TFTH00/ref=cm_sw_r_awd_qTP6ub1C5KF6H
https://www.amazon.com/dp/B000TFTH00/ref=cm_sw_r_awd_qTP6ub1C5KF6H


This stuff worked wonders for me

[DMCMW Dave]

Is it correct to say that all aftermarket headers use the opposite holes in the engine to mount?

Ours (DMCH) does. You'll have to do some research on the others. "All" is a big word.

[Trstno1]

Update!

Though I was really nervous to start tackling the exhaust manifold removal after all of my other bad luck, I am pleased to report that I was able to take off the drivers side with only one stud breaking on me. Luckily there was enough stud left to grab onto to get it out!

One side down, one to go..... :wrenchin:

Btw, who sells the stainless studs/nuts/crush washers?

[PJ Grady Inc.]

We do. See the thread above yours in FAQ.
Rob Grady
Update!

Though I was really nervous to start tackling the exhaust manifold removal after all of my other bad luck, I am pleased to report that I was able to take off the drivers side with only one stud breaking on me. Luckily there was enough stud left to grab onto to get it out!

One side down, one to go..... :wrenchin:

Btw, who sells the stainless studs/nuts/crush washers?

[Trstno1]

Another update!

I am happy to report that the passenger side exhaust manifold surprisingly came off with no issues, even the studs from the engine block..... :jawdrop: Now I just need to figure out who's exhaust system I'm saving for......

Do you guys re-use the heat shield for the starter, or is there a non-asbestos aftermarket one available?

[DMCMW Dave]

Another update!

I am happy to report that the passenger side exhaust manifold surprisingly came off with no issues, even the studs from the engine block..... :jawdrop: Now I just need to figure out who's exhaust system I'm saving for......

Do you guys re-use the heat shield for the starter, or is there a non-asbestos aftermarket one available?

http://store.delorean.com/p-6827-heatshield.aspx

[PJ Grady Inc.]

There is a factory stainless one available that for some reason never made it onto the production cars as per Dave's link..
Rob Grady
Another update!

I am happy to report that the passenger side exhaust manifold surprisingly came off with no issues, even the studs from the engine block..... :jawdrop: Now I just need to figure out who's exhaust system I'm saving for......

Do you guys re-use the heat shield for the starter, or is there a non-asbestos aftermarket one available?

[Delorean Industries]

No heat shield required on a SPEC I system. It is always advised to ditch the stock starter and upgrade to a late premiere style.

[Trstno1]

Does anyone know how I can clean the head surface where the exhaust gasket will go? I want to make sure the mating surface will be perfect, but I don't want to hurt the heads. What sort of tool / chemicals can I use? Pics?

[Delorean Industries]

Surface contamination can be carefully dealt with via scotch brite pad and penetrating oil. Finished with cleaning off with brake clean. Make sure to plug the ports.

If there is rot present on the matting surface you will need to pull the cylinder heads and machine the surface.