so i got this code P0421

So i just got myself a 03 lancer and sadly i already got my first CEL 
the code im  getting is this P0421 Warm Up Catalyst Efficiency Below Threshold (Bank 1)
 
since i dont know a thing about my lancer yet, i wanted to see if the experienced guys in this forum can help me out
 
any suggestions would be gladly appreciated!

Catalytic converter is out. Either that or an o2 sensor. 100% positive its one of those. Im betting on the cat.

yep. the cat is out.  fairly common on the lancers how many miles do you have on the car? there is some kind of a warranty extension for certain cars that are having this problem.  i just replaced one on an 03 lancer

..go down a couple of threads.

 look at the replys to "my baby's sick".

quote:

ORIGINAL: 07outty

..go down a couple of threads.

look at the replys to "my baby's sick".

 
checked it out, thanks!
 
 
 
so what would you guys recommend?
 
an oem cat,a test pipe,or any other suggestion?
 
oh and is it bad driving around with my cat messed up?

quote:

ORIGINAL: blk n tan

yep. the cat is out.  fairly common on the lancers how many miles do you have on the car? there is some kind of a warranty extension for certain cars that are having this problem.  i just replaced one on an 03 lancer

 
95k
 
so what cat do you recommend?

dude i have the same problem but different people keep telling me different things like its DEFINITELY the header....im starting to believe that its the header that is out cause of the many people with the same problem....ima get a new header tomorrow and ill let you know what that does

yea for sure keep me updated!

there should be 2 sensors on your car one in the header and one near the Catalyctic Converter the same with the 2008 Lancer.
 
Road Race is developing the Headers for the PZEV engine. for now they're only selling the non pzev engine- Headers

@ 95k you're past the warranty extension if your car was even a part of it. i wouldnt recommend test pipe cuz you're check engine light is still gonna be on

change the 02 sensores.
 
if that does not "work" change the cat.
 
when you change a cat it is a good idea to change the 02 sensors any way.........

in the last case i had it was a necessity. the cat got so hot it seized the o2 to the housing
 

changing the O2 sensors should be pretty easy but again
what would you guys recommend me to buy?
 
autozone
oem
ebay? haha
 
and whats the running price on them?

OEM= RETAIL 312.71

Answer the damn question.
 
Get an OEM cat.
 
It is NOT the header.

haha thanks sebba..
 
 
so how much are the oem cats running?
 
would u get any significant gains with a hi flow cat/ test pipe?

There is Bosche oxygen sensor at pep boys but I don't think they make it for Mitsubishi. just try or ask Pep Boys and skip Autozone cheap products.
 
the prices vary by the way mine was $150.00 for a 99 mirage yours must be a little more expensive. but you can also buy them on line and you have to wait. make sure the vin and engine number are correct.

There is no 'e' on the end of Bosch. Anyways, they SUCK.
 
I don't know how much the stock cat goes for on that car.
 
High flow cats are a crock of **** too. A test pipe is just a piece of metal pipe to go in place of the cat. This will keep the check engine light on.

retail w/out recall pricing the cat runs over 800 bucks. PM ME YOUR VIN NUMBER! IF YOU HAVE THIS RECALL AND THE CAR IS UNDER 100K MILES YOU MAY BE ABLE TO GET A CAT. REPLACED UNDER WARRANTY!!!!!

Whaaat? Please

quote:

ORIGINAL: Sebba

There is no 'e' on the end of Bosch. Anyways, they SUCK.

I don't know how much the stock cat goes for on that car.

High flow cats are a crock of **** too. A test pipe is just a piece of metal pipe to go in place of the cat. This will keep the check engine light on.

 
so i read this post that shows how to remove the cel when you  have a test pipe/hi flow cat,
does it really work?
http://www.mitsubishiforum.com/m_94383/tm.htm
 
because in that case i would rather put a cheap test pipe than wasting a lot of money in a oem cat.
 
or not?
 
damn this code!!
 
 

Sebba you dont have to embarass me...just a type O
 
We are here to help not to criticize.
 
 

quote:

ORIGINAL: blufabric

quote:

ORIGINAL: Sebba

There is no 'e' on the end of Bosch. Anyways, they SUCK.

I don't know how much the stock cat goes for on that car.

High flow cats are a crock of **** too. A test pipe is just a piece of metal pipe to go in place of the cat. This will keep the check engine light on.

so i read this post that shows how to remove the cel when you  have a test pipe/hi flow cat,
does it really work?
http://www.mitsubishiforum.com/m_94383/tm.htm

because in that case i would rather put a cheap test pipe than wasting a lot of money in a oem cat.

or not?

damn this code!!

 
i don't think this will fix your problem

It wasnt intended to call you out, im just a Nazi about that **** : ) It was a note for future, thats all lol.
 
Im not sure if that will work for your car, it has worked for DSMs though. If you did this, your car wouldn't pass emissions by the way.

^ failing emmisions is why i'm saying as well it wouldnt work. in az it might. they don't roll the cars here if they have OBD2. they just scan the 'puter.
 
 
ps... its nice to have a spelling nazi here. i'm a grammar gastapo. my first post was rippin somone a new one for calling it a "supra charger"