Catalyst General Failure

Hi all,



Been advised to post this as a new thread, so here goes:



I have recently had a new stainless steel exhaust system fitted (exhaust manifold back) including a new cat (aftermarket, I assume, not OEM) However, about a week after the system was installed, the dreaded EML light came on. T4 diagnostics showed 'P0420 Catalyst General Failure'. After resetting the stepping and fuel adaptions, and clearing the fault codes, the EML light came on again a few days later. Took car back to exhaust dealer, who moved an 02 sensor because it was too close to the cat and therefore getting too hot. This seemed to fix it, but after a 200 mile run this week, the EML light is back on again and I am back to square one. The exhaust dealer claims the cat has passed an emissions test and there's nothing wrong with it, so I don't know if they will sanction a replacement under warranty as it does not seem faulty. So I have 3 questions - what are the chances of a faulty 02 sensor, can an O2 sensor be cleaned, and is there a secondary upstream cat in the Rover 45 1.6 that could be faulty (and how would I know?) Thanks in advance, JTizzle.

from the last news http://forums.mg-rover.org/showthread.php?t=723497&goto=newpost

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