PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

SES Light..code P0430?

Thread Tools
 
Search this Thread
 
Old Jul 25, 2004 | 05:23 AM
  #1  
Mike8622's Avatar
Thread Starter
Teching In
 
Joined: Mar 2004
Posts: 14
Likes: 0
Default SES Light..code P0430?

Went to autozone and they scanned...P0430 came up. Guy checked my air filter and said I needed it replaced(he was right). He reset the light and I got the air filter...everything was fine. 25 minutes later while I'm driving the SES light comes back on. What causes this code...how do I fix this? Thanks in advance. I'm going on a short trip in bout 8 hours til tues. about 350miles each way...wanna make sure everythings cool.
Reply
Old Jul 25, 2004 | 05:41 AM
  #2  
Mike8622's Avatar
Thread Starter
Teching In
 
Joined: Mar 2004
Posts: 14
Likes: 0
Default

From what I've read on here it's the Catalytic Converter Low Oxygen Storage code...wtf does that mean? How do I fix this?
Reply
Old Jul 25, 2004 | 05:58 AM
  #3  
Mike8622's Avatar
Thread Starter
Teching In
 
Joined: Mar 2004
Posts: 14
Likes: 0
Default

Also, I have a jet hot longtubes(no air/egr fittings) and magnaflow catback NOT INSTALLED. If I were to get these put on could I run without cats? would that then bypass whatever it is I would have to do so they don't throw the codes I'm getting now? please help.
Reply
Old Jul 25, 2004 | 06:14 AM
  #4  
deezel's Avatar
TECH Regular
 
Joined: Nov 2003
Posts: 434
Likes: 0
From: Dallas
Default

p0430 catalyst efficiency below threshold

This code is usually caused by exhaust modifications (removing cats, long tube headers, etc.). If you still have your stock exhaust system, then it could be a bad O2 sensor or a bad cat converter on passenger side (bank 2).
Reply
Old Jul 25, 2004 | 06:18 AM
  #5  
Mike8622's Avatar
Thread Starter
Teching In
 
Joined: Mar 2004
Posts: 14
Likes: 0
Default

Originally Posted by deezel
p0430 catalyst efficiency below threshold

This code is usually caused by exhaust modifications (removing cats, long tube headers, etc.). If you still have your stock exhaust system, then it could be a bad O2 sensor or a bad cat converter on passenger side (bank 2).
so a local shop or mechanic can diagnose and correct the problem? my parents are cops and i ususally use the head police mechanic for my car, you think he could replace this? if not i guess to a dealer I go, but apparently it's under warranty? my car is out of warranty though.

im thinking if i have to pay for a new cat i would rather install the LTs and exhaust with a custom y with no cats...that would work to right?
Reply
Old Jul 30, 2004 | 06:21 PM
  #6  
Catskynr's Avatar
On The Tree
 
Joined: May 2003
Posts: 106
Likes: 1
From: Apache Junc, Az
Default

Common with LTs and hi-flows. If you have NO CATS, ya, that’s it. I just got done doing a write up. Check it out, it should help.
https://ls1tech.com/forums/pcm-diagnostics-tuning/195774-just-gutted-cats-wonderful-check-engine-light-any-homemade-tricks.html

420/430 codes are just too much HC in the exhaust, which = >0.045V on the rear O2s.

Also as for warranty, emmisions are a FEDRAL STANDARD that the dealer warranty them for 75K miles. If your below that and stock, take it in! If the cat is bad, they are responsible not you. That saves you some $$$$.

Last edited by Catskynr; Jul 30, 2004 at 06:29 PM.
Reply
Old Jul 30, 2004 | 06:30 PM
  #7  
Camaro SS 2002's Avatar
TECH Regular
 
Joined: Feb 2003
Posts: 430
Likes: 0
From: Pasadena, CA
Default

Originally Posted by Catskynr
Common with LTs and hi-flows.
420/430 codes are just too much HC in the exhaust, which = >0.045V on the rear O2s.
I have LT's and Magnaflow cats and I got code p0420. I initially though it was a bad cat, but it's probably too much HC in the exhaust like stated above.
Reply
Old Jul 30, 2004 | 09:45 PM
  #8  
jimmyblue's Avatar
Moderator
iTrader: (11)
 
Joined: Mar 2002
Posts: 12,604
Likes: 7
From: East Central Florida
Default

That's a rear O2 code, you have none I reckon.
On headers? Get it turned off or put sims.
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-1

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-2

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-3

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-4

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-5

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-6

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-7

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-8

10 Camaros You Should Never Buy

 
story-9

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo




All times are GMT -5. The time now is 07:54 PM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE