Hi All,

I have a new MagnaFlow high flow catalytic converter in my 2001 Civic EX. The CEL keeps comming back with a P0420 so I've followed the internet instructions on the spark plug defouler trick.
After a few drive cycles the CEL comes back on even after I disconnect the battery and "learn" the new idle proceedure.

Does anyone have good experiance with electronic O2 Simulators? Does anyone else know/share my painfull experiance with the defoulers? Is there something I'm missing?

Thanks for the help!