i got code P0420 catalyst efficiency below threshold (blank1). Does anyone know what that means? I did drive home from the beach that day about a 4 hour drive. The mods i have is a header hi flow cat and a cat back and an intake. i deleted it and it has come back.
means the cat converter isn't working correctly, or the o2 sensor in it is bad.
I've been having that issue lately. mine seems to be a gas issue. if I get gas at some gas stations, it'll set it off. others won't.
Desert Tuners
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