Fen wrote:The only cat failure I have ever had was a rattling one (which still worked). Other than that I have had a few O2 sensor failures and it's usually the front (hotter) one that goes though it could be the rear one. Just as likely the replaced front one has gone again though I expect.
Thats the part where I am like should I change both O2 sensors. I know one was changed about 15/18 months ago, but who knows. Or be logical and change the rear one first and see if the code returns.
Fen wrote:The only thing that should break the cat would be dirty fuel, so if you're confident about the quality of all the petrol you've puth through it then it should be OK.
Well I normally get fuel from BP or Shell, unless they have received a bad batch (it does come from the same refinery at Marsden point) it is unlikely. Haven't done any out of city fill-ups so chances are low of bad/old fuel.
Fen wrote:I'd leave it and see if it happens again and if it does then look at the O2 sensors.
edited to add: None of my failures have been on a Jeep, but no reason it should be different for Jeeps. I guess dumping a red-hot cat in water won't do it any good, but I'd expect that to make it rattle as it would cause physical damage rather than loss of efficiency.
My last failure was exactly that, hot cat dipped in cold mud = physical implosion of internal mesh. Having said that, on a TJ cat converter sits next to the transfer above the skid plate - it is well protected from physical bashing from elements. Well my quest will continue.