2001 dts p0420

Cadillac Forums | Help Us Help You | Advertise | Cadillac Parts | Cadillac News | Cadillac Classifieds

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 2 of 2
Northstar Engines and System Technical Discussion Discussion, 2001 dts p0420 in Cadillac Engine Discussion; I just bought a 2001 DTS and when I took it WOT the first few times my friend, who was ...
  1. #1
    Papi_MaC's Avatar
    Papi_MaC is offline Cadillac Owners Member
    Automobile(s): 02 Escalade/ 01 DTS/ 95 ETC (For Sale)/SOLD 90 92 95 DeVille
    Join Date
    Dec 2006

    2001 dts p0420

    I just bought a 2001 DTS and when I took it WOT the first few times my friend, who was tailing me, told me that there was black smoke coming out of the exhaust when I punched the gas. After checking the codes and seeing P0420 and C0662 (Current), I hoped it was a bad FPR pushing a rich fuel mix.; while also hoping it wasn't the Catalytic Converter. I changed out the FPR and the engine runs just fine and no more black smoke, from what I can see; but, while idling every once in awhile the "Service Engine Soon" light will illuminate and the idle will become shaky. I will run the codes and P0420 (C) comes back but as soon as I clear the codes, the idle is completely normal. Any thoughts?

    P.S. Before changing the FPR I was getting an average of 11mpg (city) in 90 miles; after I am getting 19mpg (city) in 40 miles.

    In addition; the "Service Stability System" message comes up a lot along with ABS C1214 C1248 and C1295; usually they read as history, but occasionally they read as current. I read that this could just be a faulty EBCM module ($150 to fix).

  2. Remove 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
    Woodstock Ill.

    Re: 2001 dts p0420

    You check the FPR by pulling the vacuum hose at idle. If fuel leaks from it, it's bad. If not, it's good. If your mileage improved, I'd suspect it was leaking and adding to the carbon in the chamber and exhaust (running rich).

    The black smoke you saw was likely carbon being cleaned out of the combustion chamber and exhaust system.

  4. Remove Advertisements
    Cadillac Forums

+ Reply to Thread

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.

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

Please enter a valid email address for yourself.

What Cadillac(s) do you own? (Or type NONE)

Please select your insurance company (Optional)

Your date of birth and age are displayed in several places on the forum. Only the administrator will have access to your date of birth should you choose to hide it via the privacy option below.


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.


Cadillac Posting Rules

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts