i have got this code steady and i cant get rid of it it says
catalyst warm up efficiency below threshold (bank 1 ) p-0421
anyone know what that is in laymans terms?
i searched but didnt come up with anything

 

do you have a header?

If not then the cat in your stock header is shot, time for a new one.

one of your cats is either missing or dead. that is what that code is.

 

Efficiency below threshold = something isn't doing its job.

I'd say the same thing Vince did. If big words like "efficiency" and "threshold" are too much for you, you may wanna read a book.

 

Check for leaks?

 

maybe let your car warm up for like 5mins before you drive it? I think I've heard of this one before..

 

i probably know more words than anyone i know thanks
but warm up efficiency? does that mean it warms up to slow or once it warms up it isnt working properly? wow usually people on this site arent civic-esk flamers right off the bat

 

the cold start cat(exhaust manifold)/header is prolly the one that is broken/shot or missing like the other have said....

 

ok hmm so i might as well get a header and down pipe and live with the cel then...
cool thanks
i knew if anyone knew then someone on here would!

 

Twas just a joke, my good man. It's not impossible that you've actually depleted your catalyst. How many miles are on the car? Does it the exhaust smell particularly strongly if you rev the car in neutral/park? While you could have an exhaust leak, and cold start could be the issue as well, there are certainly multiple possibilities.

BTW, If your catalyst is depleted and you do get a header, your exhaust is going to be BLACK and STINKY. Just some words of warning.

 

ya sorry about getting my back up...was a rough day, anyway i only have 50 000 kilometers on it that should be far from the point where you lose a cat. as to the header and stuff actually i was thinking about getting that hi flow cat from rrm as well but one think at a time i not made of money.. lol. Anyway thanks for the help guys