For reference: P0546 - Exhaust gas temperature sensor circuit high input
i rarely drive on the highway..and by rarely i mean very very rarely. the other day i drove to the beach and on the way there (after cruising for about 45 minutes or so in fifth at approx. 3000 rpm) the cel came on. i had it checked and cleared (P0546). it came back on on the way home. i have a 2003 wrx with catted tbe, uppipe, intake, mbc, and a protune via opensource. Any ideas as to what this means? I have driven on the highway only a few other times and each was for shorter (approx. 30 min.) periods at less rpms (~2500). thanks a lot!