Today I replace the catalytic converter on Twiglet the Twingo
From about halfway to Antwerp from Manchester there was a rattling loise from underneath Twiglet. By the time we got to Antwerp it was really rattling when the revs varied on the engine.
Eventually went away but P0420 and P0136 codes came up recently when engine light came on. Suspected the catalytic converter has failed and i was right but i didn't expect it to fail so badly.