hey i got the code P0420 yesterday. i have a grimmspeed gesi downpipe, and i know thats the issue, im just curious if its fine to drive with the code cleared for a couple weeks until it gets pro tuned which i hope will solve the problem
C CaTiRo79 · Registered Joined Sep 22, 2022 · 180 Posts #4 · May 10, 2023 View full thread Interesting, I thought the whole reason to get the gesi j pipe was to prevent the code.