I gather that in order to get the headers off, you first need to remove the oxygen sensor. How is this easily done? It looks like it's stuck on pretty well, unfortunately

I've already rounded the back one off (i.e. rear cat), and I don't want to do the same to this one. I used one of those rubbish adjustable spanners, so not doing that again :-)

Also, is the rear oxygen sensor really needed? I seem to recall that this is only there to measure the rear cat effeciency, but the rear cat will be replaced anyway.


Is it just a case of getting an open fixed spanner of the right size (is it 22mm), using lots of wd40 and hoping for the best? If I were to round the nut off, how much is a new one if I end up having to drill it out?

 

Come on, people Someone must have had this problem before