O2 Sensor removal nightmare
06-07-2001, 05:29 AM
#1
Addict
Rennlist
Lifetime Member
Rennlist
Lifetime Member
Thread Starter
O2 Sensor removal nightmare
I finally got round to replacing my O2 sensor yesterday, without the results I was expecting..... Pretty quickly we discovered that the Cat and it's shield had probably not been touched since it's installation in '92 (Euro/ROW car with Cat retrofit).
Two of the shield bolts refused to release so we managed to grind those off, to be faced by the O2 sensor refusing to budge an inch..... cut a long story short after several hours of cajoling, lubricating, heating we finally mangaged to turn the @£^&£$^& off - but no thread left.
So i now have a ten year old cat with a hole in it!! I've ordered a stainless steel sports pre silencer with O2 thread as an immediate fix - here in the UK an '87 car doen't need emmissions testing - I'm informed that the existing cat O2 hole can be rethreaded should testing become compulsory at a later date - but I wonder whether a ten year old cat is really doing anything and worth keeping?
Not having considered the exhaust system in any detail up to now, what do you guys recommend as a more long term solution - I'm not wanting huge track performance or loud noise - just good stainless steel that comes off when you want it to......
Two of the shield bolts refused to release so we managed to grind those off, to be faced by the O2 sensor refusing to budge an inch..... cut a long story short after several hours of cajoling, lubricating, heating we finally mangaged to turn the @£^&£$^& off - but no thread left.
So i now have a ten year old cat with a hole in it!! I've ordered a stainless steel sports pre silencer with O2 thread as an immediate fix - here in the UK an '87 car doen't need emmissions testing - I'm informed that the existing cat O2 hole can be rethreaded should testing become compulsory at a later date - but I wonder whether a ten year old cat is really doing anything and worth keeping?
Not having considered the exhaust system in any detail up to now, what do you guys recommend as a more long term solution - I'm not wanting huge track performance or loud noise - just good stainless steel that comes off when you want it to......
06-07-2001, 11:42 AM
#2
Advanced
Join Date: Jun 2001
Location: Atlanta, Ga
Posts: 63
Likes: 0
Received 0 Likes
on
0 Posts
Christian- since you don't have emmission testing why not install a cat test pipe instead of a cat itself? They come in SS, have pre-threaded holes for the O2 sensor, and are not all that expensive. As a bonus you MIGHT get better performance than a new cat! Good luck, Sean. 
06-07-2001, 12:24 PM
#3
Instructor
Christian,
Your experience mirrors mine exactly. Check the hole in the cat. You may be able to get a suitable tap and re-thread it. In my case, it was the threads on the o2 sensor that disintegrated, the ones on the cat were fine.
Keep the cat for the future. They are expensive. Shake yours...if it doesn't rattle, it's probably still good. The test pipe is a good idea. I have one in S.S. and it reduces engine temps, and increases power a little bit.
Your experience mirrors mine exactly. Check the hole in the cat. You may be able to get a suitable tap and re-thread it. In my case, it was the threads on the o2 sensor that disintegrated, the ones on the cat were fine.
Keep the cat for the future. They are expensive. Shake yours...if it doesn't rattle, it's probably still good. The test pipe is a good idea. I have one in S.S. and it reduces engine temps, and increases power a little bit.
06-07-2001, 01:04 PM
#4
Addict
Rennlist
Lifetime Member
Rennlist
Lifetime Member
Thread Starter
Thanks Guys - I think that the Stainless Steel "Sports Pre Silencer" that I've ordered is the same as the test pipe you're recommending - basically a simple pipe with the O2 hole threaded at the heat exchanger end.
I'm just praying that when we attack the exhaust system on Saturday morning the rest of the existing pipework is OK. I've ordered new gaskets and bolts so fingers crossed.
As a longer term solution, have you changed the rest of the system? The back box and heat exchangers will go eventually (especially in this wondeful Scottish Climate), I'm not after anything really trick, just a good stainless system that fits and works well - any recommendations?
Many thanks again
I'm just praying that when we attack the exhaust system on Saturday morning the rest of the existing pipework is OK. I've ordered new gaskets and bolts so fingers crossed.
As a longer term solution, have you changed the rest of the system? The back box and heat exchangers will go eventually (especially in this wondeful Scottish Climate), I'm not after anything really trick, just a good stainless system that fits and works well - any recommendations?
Many thanks again
06-07-2001, 01:51 PM
#5
I recently (two weekends ago) removed the complete exhaust sytem from my 85 930. I'm pretty sure this system has never been removed. I can recommend a good soak in a penetrating oil (I soaked for three days). Also if you can't get the nuts to loosen after this you can try heat... I got 50% of mine to come off (with a lot of work). Snap-on and some other tool companies sell "nut splitters". I found these too late in the process. I used one on a couple of bolts. It works great. Given I am planning on replacing my hardware I would have saved myself a boat load of time and frustration and just used one of these on all the fastners I could.
Hope this helps.
-LeoD
Hope this helps.
-LeoD
