Hello, Ride a 2001 MX-5 1.6, which I bought with a luminous MKL. According to the seller, the previous one was driven with a broken ignition coil for too long, which destroyed the original catalyst. That comes along, is a disease with the model, it always smelled strongly at the traffic light after oldtimer and had the P0420 (and otherwise nothing) in the error memory. Last weekend I changed the cat for a specific part of N*P. According to my understanding actually a ok brand, even if he The smell at the traffic light was done, but after 300 km the MKL went on again yesterday. So just read out again, again (only) P0420. The lambda probe signals look wonderful in idle mode m.M.n. (Fig. 1), at increased speed of about 2500 rpm (Fig. 2/3) no more, since it strikes aftercat probe synchronously with. KGE disconnect, that was always the trick 17 for the AU with my Ex-MX-5 NA, changes it also nix. Long story short, it may be that s o a new cat has to be ‘taken in’, so its effect has to be built up first? Or is the brand new thing from the pack of scrap? Or is there another factor that I just forget? Merci