C6 Corvette General Discussion General C6 Corvette Discussion not covered in Tech
Sponsored by:
Sponsored by: Feral Industries

Check Engine Light

Thread Tools
 
Search this Thread
 
Old Jul 2, 2019 | 05:04 PM
  #1  
George W Young's Avatar
George W Young
Thread Starter
Intermediate
15 Year Member
 
Joined: Oct 2004
Posts: 25
Likes: 4
From: Miami, Fl
Default Check Engine Light

I went to the Chevy dealer to find out why my check engine light is on
and he told me it was because of code # PO420 and my cats were no
good. Quoted about $2600 to replace them.
Anyone else had this problem?
My car only has a little less than 23,000 miles. The car is an '05 C-6 Z-51
black coupe and it runs great. The cats may be bad, but you can't tell it by
the way the car runs. A friend suggested to replace the oxygen sensor first
and see if that fixes it.
Would appreciate any suggestions.
Reply
Old Jul 2, 2019 | 05:42 PM
  #2  
RicK T's Avatar
RicK T
Team Owner
10 Year Member
 
Joined: Sep 2005
Posts: 20,352
Likes: 568
From: Ventura County, Calif
Default

P0420 is only one cat, driver's side I think, the other side is 0430.

Be sure the oxygen sensor is good before committing to a cat. Look in here for a couple ideas:

https://www.corvetteforum.com/forums...0420-code.html
Reply
Old Jul 2, 2019 | 06:10 PM
  #3  
Landru's Avatar
Landru
Race Director
20 Year Member
Veteran: Army
Liked
Community Favorite
 
Joined: Dec 2002
Posts: 10,468
Likes: 1,149
From: Wayne Township WI
Default

Had same issue Jan of '19. '08 Z06 w/ 60K.
Z06 forum folks thought losing a CC @ 60K incredulous. 02 sensor yes, those can go bad.
But a CC?
Dealer said so, had me by the shorthairs.

Best of all as-of 01/19 OEM CCs were on national backorder.
SA w/couldn't give a time they'd be available. 1 week-month-year?
They suggested an aftermarket CC c/would work fine, <$ than OEM and they'd even warranty it as-if OEM.
Wanted my damned Z back before 2020-2021 so told 'em go ahead. Bill was ~$1,700.

Here's the joker, tho' performance is unaffected I swear AM CC altered exhaust tone -- and not for the better.
Used to have a sharp performance note on accel and nice controlled rumble/pop on decal.
While accel still sounds good on decel it bellows, only way sound can be described.
In fact sounds just like the old 60s era BB Chevys did only It's a LS7 & these motors are supposed to sound fabulous.
Mine did for past 11 years prior to CC. I mean WTF.

Can go aftermarket for CCs but don't be surprised if it alters exhaust note, either.
Reply

Get notified of new replies

To Check Engine Light





All times are GMT -4. The time now is 06:34 AM.

story-0
5 Best & 5 Most Overrated Corvette Track Packages of All Time!

Slideshow: The 5 best and 5 most overrated Corvette track packages ever.

By Joe Kucinski | 2026-06-09 12:46:45


VIEW MORE
story-1
Every 2027 Corvette Engine Explained

Slideshow: Every 2027 Corvette engine explained

By Joe Kucinski | 2026-06-09 12:16:31


VIEW MORE
story-2
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette

Slideshow: A Jaguar designer's personal project imagines what a modern front-engined Corvette might look like if Chevrolet revisited the golden age of the Stingray.

By Verdad Gallardo | 2026-06-08 19:53:43


VIEW MORE
story-3
10 Ugly Corvettes That We Still Kinda Love

Slideshow: 10 ugly Corvettes that we still kinda love.

By Joe Kucinski | 2026-06-03 10:34:17


VIEW MORE
story-4
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

A lot of money has changed hands at the online auction house over the years.

By Brett Foote | 2026-06-03 10:21:50


VIEW MORE
story-5
10 Things Every Corvette Owner Needs (2026 Edition)

Slideshow: 10 great gifts Corvette enthusiasts actually want for Father's Day!

By Michael S. Palmer | 2026-06-03 15:43:40


VIEW MORE
story-6
8 Most "Only Corvette Owners Understand" Quirks and Problems

Slideshow: These are the quirks, annoyances, and oddly lovable problems that every Corvette owner eventually learns to live with.

By Pouria Savadkouei | 2026-05-28 09:31:39


VIEW MORE
story-7
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

Slideshow: 10 reasons why the C6 Z06 is still a performance benchmark after 20 years.

By Joe Kucinski | 2026-05-27 17:20:09


VIEW MORE
story-8
How Much Horsepower Every Corvette Engine "LOST" in 1972

Slideshow: How much horsepower every Corvette engine lost in 1972.

By Joe Kucinski | 2026-05-27 16:54:53


VIEW MORE
story-9
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

Slideshow: How to Protect A Convertible Top: 10 DOs & DON'Ts

By Michael S. Palmer | 2026-04-03 00:00:00


VIEW MORE