PCM Diagnostics & Tuning HP Tuners | Holley | Diablo
Sponsored by:
Sponsored by:

Code p0420

Thread Tools
 
Search this Thread
 
Old 03-25-2007, 09:01 PM
  #1  
Launching!
Thread Starter
iTrader: (3)
 
WS SIKZ's Avatar
 
Join Date: Feb 2007
Posts: 200
Likes: 0
Received 0 Likes on 0 Posts
Default Code p0420

code p0420 catylist efficiency low bank one
is it cat or the o2 sensor didnt lookinto it yet code came one today braught it to my shop and im gonna look at it tomarrow but have you had any experiance with this or weich problem it is?
Old 03-25-2007, 09:24 PM
  #2  
TECH Fanatic
iTrader: (1)
 
taintedmeat's Avatar
 
Join Date: Apr 2005
Location: ATX
Posts: 1,625
Likes: 0
Received 0 Likes on 0 Posts
Default

Could be either one. If you're under 80k miles I'd take it to a stealership and get your cat replaced for free under federal warranty. If it still does it after that, throw in a new o2.
Old 03-25-2007, 10:21 PM
  #3  
10 Second Club
iTrader: (25)
 
03 BUSA's Avatar
 
Join Date: Dec 2004
Location: Kannapolis, NC
Posts: 2,554
Likes: 0
Received 1 Like on 1 Post
Default

Bank one is the left side. That code is usually for the o2 sensor, not the cat. Again that is in most cases I have seen.
Old 03-25-2007, 11:16 PM
  #4  
TECH Fanatic
iTrader: (5)
 
joshp14's Avatar
 
Join Date: Dec 2003
Location: WDM, Iowa
Posts: 1,108
Likes: 0
Received 0 Likes on 0 Posts

Default

Originally Posted by 03 BUSA
Bank one is the left side. That code is usually for the o2 sensor, not the cat. Again that is in most cases I have seen.
I am going to disagree with you....in my experience at the dealership a P0420 is 100% a cat failure. I've replaced several for that code on the f-bodies....mostly the P0420 for drivers side, but I have had a few P0430 for the passenger side. GM also released a special policy for the 00-02 f-bodies that extends the warranty from 8yr/80k to 10yr/120k.

WS SIKZ,

If you fall under the 8yr/80k, take it to the dealership and tell them you think it's a cat problem. They will diagnose it, verifiy its the cat, and order you one. Hell if its a pontiac dealership they may have one in stock.

-Josh
Old 03-25-2007, 11:26 PM
  #5  
On The Tree
iTrader: (1)
 
jason1384's Avatar
 
Join Date: Mar 2007
Posts: 171
Likes: 0
Received 0 Likes on 0 Posts
Default

I also got a P0420 and a P0430 code. If i take it to the dealership to be replaced and they scan it, do they charge you for the scan?
Old 03-26-2007, 09:18 AM
  #6  
Launching!
iTrader: (2)
 
MY02REDWS6TA's Avatar
 
Join Date: Jun 2006
Location: Powell, Ohio
Posts: 236
Likes: 0
Received 0 Likes on 0 Posts

Default

P0420 is a bad driver's side cat. I had this code right after I got the car last Summer before the LT install. Went to the dealer, they scanned it and replaced the drivers side cat. Absolutely no charge.
Old 03-26-2007, 12:31 PM
  #7  
Launching!
Thread Starter
iTrader: (3)
 
WS SIKZ's Avatar
 
Join Date: Feb 2007
Posts: 200
Likes: 0
Received 0 Likes on 0 Posts
Default

ok thanks
Old 03-26-2007, 12:41 PM
  #8  
TECH Senior Member
 
2001NBMZ28's Avatar
 
Join Date: Dec 2001
Location: Jacksonville, FL
Posts: 5,399
Likes: 0
Received 3 Likes on 3 Posts

Default

Originally Posted by jason1384
I also got a P0420 and a P0430 code. If i take it to the dealership to be replaced and they scan it, do they charge you for the scan?
Friend of mine had his drivers side replaced free under warranty - no charge for the scan if they diagnose the cat(s) as the problem. He didn't clear the code - left the SES on.
Old 03-26-2007, 12:52 PM
  #9  
TECH Veteran
iTrader: (7)
 
Sharpe's Avatar
 
Join Date: Aug 2004
Location: Southeastern IL
Posts: 4,997
Likes: 0
Received 1 Like on 1 Post
Default

I thouhgt code P0420 was for smoking too much bud in your car and getting it all smogged up.
Old 03-26-2007, 11:14 PM
  #10  
On The Tree
iTrader: (1)
 
jason1384's Avatar
 
Join Date: Mar 2007
Posts: 171
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by 2001NBMZ28
Friend of mine had his drivers side replaced free under warranty - no charge for the scan if they diagnose the cat(s) as the problem. He didn't clear the code - left the SES on.
So they charge if they scan it and its not the cats?
Old 03-27-2007, 10:30 AM
  #11  
TECH Fanatic
iTrader: (5)
 
joshp14's Avatar
 
Join Date: Dec 2003
Location: WDM, Iowa
Posts: 1,108
Likes: 0
Received 0 Likes on 0 Posts

Default

If its not the cat they will charge for diagnosis. Like I said, EVERY f-body that has come in to the dealership I work at with the P0420 has turned out to be a drivers side cat.
Old 01-08-2008, 05:53 AM
  #12  
TECH Addict
iTrader: (13)
 
qwk93ta's Avatar
 
Join Date: Jun 2004
Location: Fairfield, Ohio
Posts: 2,240
Likes: 0
Received 1 Like on 1 Post

Default

I just got this code last night coming home from work.
Old 01-08-2008, 12:48 PM
  #13  
TECH Apprentice
iTrader: (6)
 
7901 WS6's Avatar
 
Join Date: Feb 2005
Posts: 322
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by MY02REDWS6TA
P0420 is a bad driver's side cat. I had this code right after I got the car last Summer before the LT install. Went to the dealer, they scanned it and replaced the drivers side cat. Absolutely no charge.

+1
Same for me Drivers side. my car had about 30K miles at that time too.



Quick Reply: Code p0420



All times are GMT -5. The time now is 02:39 AM.