2002 SLS Code P 0401
Cadillac
 

Cadillac Forums | Help Us Help You | Advertise | Cadillac Parts | Cadillac News | Cadillac Classifieds / (Old System)

Cadillac Technical Archive | Cadillac Dealers | Cadillac Reviews | Cadillac Dealer Reviews | Cadillac Vendors

CadillacForums.com is the premier Cadillac Forum on the internet. Registered Users do not see the above ads.
+ Reply to Thread
Results 1 to 8 of 8
Northstar Engines and System Technical Discussion Discussion, 2002 SLS Code P 0401 in Cadillac Engine Technical Discussion; Hello all and Happy Holidays! I am trying to help a friend with his 2002 SLS.. He cant pass inspection ...
  1. #1
    postman2000's Avatar
    postman2000 is offline Cadillac Owners Fanatic
    Automobile(s): 1996 STS 2000 Deville
    Join Date
    May 2009
    Posts
    253

    2002 SLS Code P 0401

    Hello all and Happy Holidays! I am trying to help a friend with his 2002 SLS.. He cant pass inspection because of the SES light on and a code P401 ( EGR System Insufficient Flow)...He replaced the egr valve with a new Delphi unit and he is still getting this code.. I have read up on this subject a little bit but I am still confused about whether there are egr passage ways in the intake or head that also need to be cleaned out.. And if there are not any, what else could be the problem..Any insight into this problem would be greatly appreciated.. Thank you all for your consideration..

  2. Remove Advertisements
    CadillacForums.com
    Advertisements
     

  3. #2
    Ranger's Avatar
    Ranger is offline Cadillac Owners Member
    Automobile(s): White Diamond '03 DHS (with DTS floor shift)
    Join Date
    Jun 2004
    Location
    Woodstock Ill.
    Age
    66
    Posts
    74,452

    Re: 2002 Seville SLS Code P401

    The EGR passages on the Northstar are in the crossover manifold and are large enough that they should never need cleaning if I remember correctly. Can't imagine what would cause that code if the EGR was replaced. How long ago was it replaced? Could it be a historical code? If so, it will clear itself after 3 ignition cycles or you can clear it yourself via the DIC.

  4. #3
    postman2000's Avatar
    postman2000 is offline Cadillac Owners Fanatic
    Automobile(s): 1996 STS 2000 Deville
    Join Date
    May 2009
    Posts
    253
    Thread Starter

    Re: 2002 Seville SLS Code P401

    It was replaced a few months ago but immediately after clearing the codes it came back the same day and has been there since..He is all of a suden paying attention to it because of the upcoming inspection..

  5. #4
    Ranger's Avatar
    Ranger is offline Cadillac Owners Member
    Automobile(s): White Diamond '03 DHS (with DTS floor shift)
    Join Date
    Jun 2004
    Location
    Woodstock Ill.
    Age
    66
    Posts
    74,452

    Re: 2002 Seville SLS Code P401

    The only thing I can think of is to pull the EGR valve again and make sure that the gasket is mounted correctly and that the base of the valve is not clogged for some odd reason.

  6. #5
    Submariner409's Avatar
    Submariner409 is offline If it won't run, stick on fender vents
    Automobile(s): 2002.5 F55 STS/65500mi, 2004 Ford F150 SuperCab4x4
    Join Date
    Feb 2006
    Location
    MD Eastern Shore - Kent Island
    Age
    74
    Posts
    45,468

    Re: 2002 SLS Code P 0401

    If the exhaust manifold feed pipe or the port from the EGR chamber in the crossover casting is/are plugged with carbon, that will set P 0401. You not only have to check the EGR motor assembly itself, upon inspection/replacement you also need to clean out all the ports.

  7. #6
    postman2000's Avatar
    postman2000 is offline Cadillac Owners Fanatic
    Automobile(s): 1996 STS 2000 Deville
    Join Date
    May 2009
    Posts
    253
    Thread Starter

    Re: 2002 SLS Code P 0401

    Thanks for the info Sub and Ranger.. Is it possible to clean the ports without disassembly? Can I use like Carb cleaner and a wire coat hanger or the like? Thanks for your help with this matter

  8. #7
    Ranger's Avatar
    Ranger is offline Cadillac Owners Member
    Automobile(s): White Diamond '03 DHS (with DTS floor shift)
    Join Date
    Jun 2004
    Location
    Woodstock Ill.
    Age
    66
    Posts
    74,452

    Re: 2002 SLS Code P 0401

    You are going to have to do some disassembly and if you find anything (I rather doubt you will), you'll probably need a coat hangar.

  9. #8
    postman2000's Avatar
    postman2000 is offline Cadillac Owners Fanatic
    Automobile(s): 1996 STS 2000 Deville
    Join Date
    May 2009
    Posts
    253
    Thread Starter

    Re: 2002 SLS Code P 0401

    Ok I will try to take this thing apart and see if I find any chunks of carbon in there... Thank you guys for your help.

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.
If you do not want to register, fill this field only and the name will be used as user name for your post.

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

Please enter a valid email address for yourself.

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Bookmarks

Cadillac Posting Rules

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
Read about Lincoln | Buick | Kia Forte Forum
Need products for your Cadillac? Check out your options at the links below:

custom floor mats | Cadillac Chrome and Black Chrome Wheels | window tinting