any ideas on how to remove the nut that holds the lambda sensor to the downpipe, as it is or seems to be welded to the exhaust at one end, and attached to the wire at the other ( it will disconect from the front, and i could remove it if i wanted to remove the entire cooling system???,) i was on for 2 hours trying to remove that blooming nut, i heated it, spannared it and eventually hit it with my hammer, but to no avail, grrrrr, would some one please tell me you can undo the unit with out having to do disconnect the cooling system, hopefully it removes from the back????, here's hoping, lol, first time ever i want to have a blond moment

thanks in advance guys, any advice is appreciated

normally the mounting boss for the sensor is welded to the pipe, then the sensor is screwed into it, you'll need a deep 22mm socket with a window on the side to allow the cable out, when they've been in there a few years they can sieze in completely if you are unlucky. it's possible that in the past the probe may have been welded in if there were a leak of some sort.

i remember having to completely remove the cylinder head on a renault megane because i couldn't undo the probe, and i couldn't take off the manifold (probe was in manifold) without taking the probe out first. i tried everything, in the end I ended up drilling out the probe... nasty nasty job

i will have another go today, i can see me putting the other sections of the exhaust on then taking it to a garage for them to do, hehe cheeky or what......

I got it by spraying some WD40 and let it overnight, but someone else told me about a better penetrating liquid. Cant remember the name, got it in AllFrauds, it is call something like "Shock bolts"...