jinxeng

Hey guys
I have a 2000 Camaro Z28 with about 35k miles

I linked my car with the OBD 2 and got a P04020 code, Catalyst Efficiency Below Thresold (Bank 1)

Does anyone know what that means ? I have yet to so my spark plugs which I will today. 3 Days before the code went up, I seafoamed my car. Any clues ? As always, Thanks

staringback05

iTrader: (8)

sounds like your cat is jammed, or corroding....when you seafoam a car, it will free up ALOT of crap which in turn will get stuck in your cats....sad to say, i think u just sacrificed cleaning the internals for the sake of one of your cats....

2001NBMZ28

Drivers side cat - with only 35K it's covered under warranty, don't know if the seafoam will void it or not. Sometimes they just go bad - GM just extended the warranty on mine from 8yrs/80K to 10/120 on mine - people are getting letters in the mail.

jinxeng

i just passed smogged... so what are the negative effects of having a plugged up cat, besides the obvious, passing smog.
i'm thinking about getting LT with a Y pipe later next year but are there any major negative effects to my engine and all. thanks

01WS6/tamu

iTrader: (37)

get it fixed if it's melting it will kill performance, warranty will cover it to 80k miles

performabuilt

iTrader: (25)

Yes it should be under warranty and dont mention the sea foam in warranty dealing as little information as possible is generally best particularly with a dealer ship
FYI

taintedmeat

iTrader: (1)

It might just be temporary. Possibly just the burning off of the Seafoam residue set it off. Would suck if you lost one of your cats from Seafoaming, especially with such low miles

CULATR

iTrader: (96)

sounds like you fall under the letter everybody's getting in the mail for the cats problem check out the thread on here .........https://ls1tech.com/forums/general-maintenance-repairs/621096-service-bulletin-letter-mail.html