Go Back   DodgeForum.com > Dodge SUVs > Dodge Durango > 1st Gen Durango
Sign in using an external account
Register Forgot Password?


1st Gen Durango 1998 - 2003 Durango's

Error code P0420, What do I do?

Reply
 
 
 
 
Thread Tools Search this Thread
  #1  
Old 01-05-2008, 12:01 PM
scientist scientist is offline
Rookie
Garage is empty, add now
 
Join Date: Jun 2007
Location:
Posts: 54
Default Error code P0420, What do I do?

OK, I got an error code P0420 Catalyst System Efficiency Below Threshold (Bank 1), what do I do now? I got the error code only when the weather temps were 10 or more degrees below zero. I don't want to change the cat converter if it is something simple like replacing and oxygen sensor or such. Any suggestions?
This ad is not displayed to registered and logged-in members.
Register your free account today and become a member on Dodge Forums!
__________________
2000 5.9 Durango-250K SSteel Borla Cat back;K&N Intake;MSD coil(8228) Champ Iridium (9203);K&N Oil Filter (HP-2004);Mobil 1 Syn 5W30(winter)10W40(summer);Gear oil 75W140; Drilled/slotted Rotors&Ceramic Pads;Edelbrock Shocks;BF Goodrich T/A KO
Reply With Quote
  #2  
Old 01-05-2008, 01:50 PM
OneBadKota OneBadKota is offline
All Star
1995 Dodge Dakota
My Garage
 
Join Date: Feb 2006
Location: New Baltimore, Mi
Posts: 933
Send a message via AIM to OneBadKota Send a message via Yahoo to OneBadKota
Default RE: Error code P0420, What do I do?

Try cleaning the sensor first. Works most the time for any sensor, if it doesn't I would probably replace it.
__________________
Reply With Quote
  #3  
Old 01-11-2008, 10:07 AM
scientist scientist is offline
Rookie
Garage is empty, add now
 
Join Date: Jun 2007
Location:
Posts: 54
Default RE: Error code P0420, What do I do?

Now I'm puzzled, replaced the sensor #1 before the cat and still getting the error code. Sensor #2 was replaced 6 months ago. Is it the gas I'm using that is causing the error becuase it is inconsistent when the check engine light goes on. One tank full and it will be fine, the next get an error code. My MPG's are fine and exhaust does not smell
__________________
2000 5.9 Durango-250K SSteel Borla Cat back;K&N Intake;MSD coil(8228) Champ Iridium (9203);K&N Oil Filter (HP-2004);Mobil 1 Syn 5W30(winter)10W40(summer);Gear oil 75W140; Drilled/slotted Rotors&Ceramic Pads;Edelbrock Shocks;BF Goodrich T/A KO
Reply With Quote
  #4  
Old 01-11-2008, 10:11 PM
durangeddurango durangeddurango is offline
Professional
Garage is empty, add now
 
Join Date: Sep 2007
Location:
Posts: 180
Default RE: Error code P0420, What do I do?

the 420 codes comes from the rear o2 sensor. the cat is basicaly a oven when there are colder temps out the cat is losing its heat and may trip a 420 code.(reason why they installed heat shieldson cats.if u are missing the heat shield this can be your whole problem in cold weather)a consistant 420 code is a sign of a catalyst deteriation meaning you are on your way to replacing the cat. if u have acces to a laser thermometer take a temp reading in front,middle,and rear of cat the temps should be around 225 degress (giveor take 20-25degrees)when fully warmed at a idle the middle of the cat will be the hottest. when the d is cold try hitting the cat with ur hand and listen for any ratteling (dont confuse this noise with a lose heat shield)if you hear any ratteling your in for a cat. option number 3 go buy spark plug antifoulers drill out the centers remove rear o2 install antifouler reinstall o2 into antifouler this may require 2-4 antifoulers to keep light off but this is only a temporary solution and if the catalyst is damaged the deteriation of the cat will lead to failure. worse case with the failure the broken catalyst will become lodged in the exhaust system rendering poor performance.
Reply With Quote
  #5  
Old 03-28-2008, 04:14 PM
Swanny Swanny is offline
Registered User
Garage is empty, add now
 
Join Date: Mar 2008
Location:
Posts: 24
Default RE: Error code P0420, What do I do?

If you use lower-quality replacement parts for things like o2 sensors, they can fail quite quickly. I've seen that many times. Did you use OEM or high-quality o2 sensors? The rear sensor could be bad again or it could be your converter. I found this link with some tips - http://www.obd-codes.com/p0420
__________________
2008 Ram SLT 4x4 - Khaki inside & out
I saved $300 and installed my side steps myself
Mods: Chrome mirror caps, chrome wheel skins, chrome cloud rider grille insert, chrome rocker trim (coming soon)
Reply With Quote
  #6  
Old 03-28-2008, 11:31 PM
hydrashocker's Avatar
hydrashocker hydrashocker is offline
Hall Of Fame
Garage is empty, add now
 
Join Date: Jun 2005
Vehicle: 99' Ram 2500 V-10 Sport QC 4X4
Location: GJ, Colorado
Posts: 14,082
Default RE: Error code P0420, What do I do?

Have you completed a back pressure check yet?

[sm=alcoholic.gif][sm=icon_guiness.gif][sm=alcoholic.gif]
It's Friday guy's!!!!!!!!
__________________

Moto: I don't take sides, I hate everyone equally --- #1 V10 Club Member V10 Club

AKA....The Durango Section Godfather
Reply With Quote
Old 03-28-2008, 11:31 PM
 
 
 
Reply




Tags
2000, 420, antifouler, antifoulers, cat, code, cold, dodge, durango, efficiency, error, obd, p0420, spark, threshold, weather

Thread Tools Search this Thread
Search this Thread:

Advanced Search

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 Off
Pingbacks are Off
Refbacks are Off

Forum Jump

Join DodgeForum
Advertising

Featured Sponsors
Vendor Directory
Our Sponsors
All times are GMT -4. The time now is 10:08 AM.

Internet Brands, Inc.


Contact Details & Emails