Finalmente I.L. MOTORSPORT mi ha risposto, ma sinceramente ci ho capito poco su da farsi !!!!!
Hello,
there are some solutions, if the
problem occurs.
P0421 "Warm up catalyst system
efficiency below threshold"
1) Modifying the hardware to get the
temperatur quicker higher. e.g. header wrap or coatings.
2) Modifying the ecu. e.g. with ECUTek
3) Simulate only the needed signal
We have tested this header in our NCFL and
had no error. Can you send us some pictures from the installed header?
Have you done other mods on your NC, which
could affect to the cat warm up? Other Sparkplugs, thermostat...?
Regards
Sandro