Check engine light code P0421?What the hell *update* - Mazda3 Forums : The #1 Mazda 3 Forum
 
LinkBack Thread Tools
post #1 of 5 (permalink) Old 07-10-2010, 07:31 PM Thread Starter
Le Mans: Prototype Class
 
Join Date: May 2007
Location: NJ
Posts: 1,735
Send a message via AIM to djv154
Check engine light code P0421?What the hell *update*

I dont know how this happened, just came on today. What the hell does it mean, thanks for all your help.

My Mazda is sold, still have an nextmod CF grill for sale. 160 OBO




Why do people get so butthurt on this site. ROFL
djv154 is offline  
Sponsored Links
Advertisement
 
post #2 of 5 (permalink) Old 07-10-2010, 09:56 PM
Moderator
 
DrWebster's Avatar
 
Join Date: Mar 2006
Location: St. Paul, MN
Posts: 3,476
Re: Check engine light code P0421?What the hell

A quick Google shows that P0421 is exhaust-related; most people say to check your O2 sensors or cat.

DrWebster is offline  
post #3 of 5 (permalink) Old 07-11-2010, 01:43 AM
Le Mans: Prototype Class
 
Join Date: Jan 2010
Location: TAMPA,Florida
Posts: 1,014
Re: Check engine light code P0421?What the hell

i think it's the first O2 sensor. that or the flux capacitor is going bad.

speed3 exhaust, simota SRI, TEIN basic coilovers, SPC camber arms, GTSPEC mid chassis midbrace, Torque Solution-RMM, awr-SMM, speed3 rear sway bar, GTSPEC Link Reinforcement Panel, GTSPEC Rear V Brace, carbon fiber speed3 replica spoiler, corksport skidplate, Rear Cross Floor bar,GTSPEC front ladder brace,GTSPEC Rear Lower Tie Brace,GTSPEC front Lower Tie Brace,Vibrant headers,GV front lip, carbon fiber open mouth grill, Viper 5904 w/SmartStart,
brunangii is offline  
post #4 of 5 (permalink) Old 07-12-2010, 03:08 PM Thread Starter
Le Mans: Prototype Class
 
Join Date: May 2007
Location: NJ
Posts: 1,735
Send a message via AIM to djv154
Re: Check engine light code P0421?What the hell

Just wondering I have a hole in my catalitic converter so for the time being I was going to take it out. I'm in FL right now so i'm going to be driving up to NJ within 2 weeks or so. Should I just keep the hole that is in my catalitic converter or just get a straight pipe for the time being while I'm in FL. Then when I get to NJ I could find a catalitic converter because I know in NJ you need one. Plus I'm going to have to deal with the CEL after I take out the catalitic converter is that right? Is there away to remove the CEL. I have an 04 mazda 3 hatch. thanks alot

My Mazda is sold, still have an nextmod CF grill for sale. 160 OBO




Why do people get so butthurt on this site. ROFL
djv154 is offline  
post #5 of 5 (permalink) Old 07-12-2010, 03:22 PM
Le Mans: Prototype Class
 
Join Date: Jul 2008
Location: Fall river, MA
Posts: 1,016
Send a message via AIM to goggles1226
Re: Check engine light code P0421?What the hell *update*

i have a 2005 and removed my Catalytic converter with no issue. no cel nothing. the 2nd CAT not the 1st...

goggles1226 is offline  
Sponsored Links
Advertisement
 
Reply

  Mazda3 Forums : The #1 Mazda 3 Forum > Technical / Model / Performance > Powertrain 2004-2009 Mazda3

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Mazda3 Forums : The #1 Mazda 3 Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Image Verification
Please enter the six letters or digits that appear in the image opposite.

Registration Image

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome