4.6l N* knocks in cold weather, but quiets after operating temp is reached.
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
Page 1 of 3 1 2 3 LastLast
Results 1 to 15 of 37
Northstar Engines and System Technical Discussion Discussion, 4.6l N* knocks in cold weather, but quiets after operating temp is reached. in Cadillac Engine Technical Discussion; I just bought a 2000 Deville, interior and exterior is immaculate. It had 104,000 miles when i bought it. A ...
  1. #1
    texas177 is offline Cadillac Owners Member
    Automobile(s): Deville 2001
    Join Date
    Jan 2009
    Age
    28
    Posts
    6

    4.6l N* knocks in cold weather, but quiets after operating temp is reached.

    I just bought a 2000 Deville, interior and exterior is immaculate. It had 104,000 miles when i bought it. A week later the temp dropped and I heard a knocking sound from the engine compartment. After the engine reached operating temp the sound faded. Now that i heard the noise i cant help but notice it. I am very familiar with ford engines, but this is my first Northstar. I took the car to Midas and had an oil change done. The car took 8 quarts of Shell 30w, after this i drove the car to Texas. The car drove good but i heard the sound in the mornings. The car has been good it only used 80 dollars of gas on a 1300 mile trip and still left half a gas tank. Please guys any advice will be appreciated.

  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
    74,524

    Re: 4.6l N* knocks in cold weather, but quiets after operating temp is reached.

    First off, it only takes 7.5 qts. (I put 7 at oil changes).

    Do a search for "cold carbon rap". Then take it out and drive it like you stole it. Read up on "Full Throttle.........." in the Technical Archives at the top left of this page.

  4. #3
    Submariner409's Avatar
    Submariner409 is offline If it won't run, install a sound system
    Automobile(s): 2002.5 F55 STS/65500mi, 2004 Ford F150 SuperCab4x4
    Join Date
    Feb 2006
    Location
    MD Eastern Shore - Kent Island
    Age
    74
    Posts
    45,549

    Re: 4.6l N* knocks in cold weather, but quiets after operating temp is reached.

    Yeah that ^^^^^ and your car uses 5W-30 oil, either dino or synthetic, whatever floats your boat, as Ranger said, 7.5 quarts MAX.

    Go up to the Cadillac Technical Archive in the black bar ^^^ and read the whole thing, particularly "Occasional full throttle is good for your engine".

    Quite a few engine changes at the start of the 2000 year.......do some homework in here and in Deville/Seville. Read up on how to pull your own Diagnostic Trouble Codes from the car's onboard system: you don't need an aftermarket scanner - too generic and miss some codes. Look on the sticker under the spare tire cover and enter all the 3-character codes into www.cadillacfaq.com/rpo/index.php to find out what's in your car. Look at the driver's door stickers to find out the build date and tire size/speed rating.

    If you get antsy to check the transmission fluid, it must be done with the engine hot running in P.....the transmission is a dry sump unit and will show NO oil on the dipstick with the engine off.

    Welcome Aboard !!!

  5. #4
    texas177 is offline Cadillac Owners Member
    Automobile(s): Deville 2001
    Join Date
    Jan 2009
    Age
    28
    Posts
    6
    Thread Starter

    Re: 4.6l N* knocks in cold weather, but quiets after operating temp is reached.

    Thanks Ranger I also googled Cold Carbon rap, and sounds consistent with my car. I will try some WOT tonight when the roads clear up, but is there some additive that can help clean the cc. Please advise.

  6. #5
    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
    74,524

    Re: 4.6l N* knocks in cold weather, but quiets after operating temp is reached.

    Yes, a heavy right foot. Give it a regular dose of WOT once a month or so. The more the better. That's all she needs. No snake oil.

  7. #6
    Necrosan is offline Cadillac Owners Enthusiast
    Automobile(s): 1994 Cadillac Eldorado Touring Coupe
    Join Date
    Jan 2008
    Location
    MKE
    Posts
    821

    Re: 4.6l N* knocks in cold weather, but quiets after operating temp is reached.

    Seafoam worked great on my Eldorado and my GFs Lincoln Mark VIII.
    The DIC on both cars reported gas mileage increases of up to 4 MPG.
    Also seemed to make the Eldo run better at initial turn on.

  8. #7
    texas177 is offline Cadillac Owners Member
    Automobile(s): Deville 2001
    Join Date
    Jan 2009
    Age
    28
    Posts
    6
    Thread Starter

    Re: 4.6l N* knocks in cold weather, but quiets after operating temp is reached.

    Well guys I did some hard accelerations in the past day. Aside from enjoying some WOT, I did get to hear sound last a little less during cold start up. My oil change is due already, and I would like some suggestions on what brand and weight. Also is Marvels mystery oil any good? I tried Lucas but it didn't do much a difference, please advise.

  9. #8
    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
    74,524

    Re: 4.6l N* knocks in cold weather, but quiets after operating temp is reached.

    The owners manual recommends 5W30. I still use 10W30. Marvel Mystery oil has a purpose, but not much any more with todays oils. It's basically a penetrating oil as I recall and will thin down you oil. It was very useful years ago for freeing up sticky lifters, but that rarely happens with todays oils. Forget it.

    There is a decarbonizing procedure where you put Techron (I think) in the cylinders and let it soak for a few hours. Then suck it out, change the oil, take it out and run it, then change the oil again. Since it is improving, maybe you just need to beat on her a little more.

  10. #9
    SPreston2001's Avatar
    SPreston2001 is offline Cadillac Owners Enthusiast
    Automobile(s): 2000 Polo Green Metallic Cadillac STS 60K
    Join Date
    Dec 2008
    Location
    Columbus, OH
    Age
    31
    Posts
    787

    Re: 4.6l N* knocks in cold weather, but quiets after operating temp is reached.

    Yeah do a few more WOT and she will purr like a kitten. You can use seafoam if you wanna clear it up faster and experience the joy of the cloud of white smoke that will pour out your exhaust!! I took the oppurtunity yesterday to let my baby stretch her legs and opened her up to 110mph on the highway!! Before you guys start ranting about how dangerous it is, we had some great weather with no traffic on a nice 5 lane stretch of highway. The only thing I was indangering was my wallet if the man were to catch me!!

  11. #10
    stoveguyy is offline Cadillac Owners Connoisseur
    Automobile(s): 03 STS
    Join Date
    Aug 2007
    Location
    mpls mn
    Posts
    2,499

    Re: 4.6l N* knocks in cold weather, but quiets after operating temp is reached.

    110 sounds like fun but how about just staying in 3rd gear? or even 2nd. that will rev the motor and keep your speed down. its like the joke where the guy got pulled over by a cop and said his alternator was dying so he had to drive fast to keep the motor spinning so the headlights would work. try 2nd gear. duh.

  12. #11
    SPreston2001's Avatar
    SPreston2001 is offline Cadillac Owners Enthusiast
    Automobile(s): 2000 Polo Green Metallic Cadillac STS 60K
    Join Date
    Dec 2008
    Location
    Columbus, OH
    Age
    31
    Posts
    787

    Re: 4.6l N* knocks in cold weather, but quiets after operating temp is reached.

    Well when I was doing 110, I was doing it more for fun and not so much trying to do a WOT. When I do my WOTs I do leave it in second and take it up to 70-75mph.

  13. #12
    codewize's Avatar
    codewize is offline Cadillac Owners Master
    Automobile(s): 1991 Brougham d'Elegance / 2001 DTS / 2002 DTS
    Join Date
    Apr 2005
    Location
    Upstate NY
    Posts
    6,681

    Re: 4.6l N* knocks in cold weather, but quiets after operating temp is reached.

    As far as I'm concerned I think a certain amount of knock is pretty normal for these engines in the cold.

    I can assure you I don't have carbon buildup and my car knocks a little in the cold weather until she's warmed up.
    Ownership:
    91 Brougham d'Elegance 350
    02 Deville DTS
    01 Deville DTS:
    Custom installed Volant CAI
    Custom PCM
    Body color engine components
    Cruiser Alloy wheels
    EBC brakes and rotors
    Eibach springs
    Corsa exhaust
    Sportwing Spoiler
    Semi-custom interior
    Custom quad Hi-Beams
    Future Plans: More interior work.


    Memberships:
    National and regional Cadillac & LaSalle Club
    Proud Volunteer - Northstar Tuning Project
    Guinness World Records - Largest Cadillac Parade

    ----------------------------

  14. #13
    STSj90 is offline Cadillac Owners Fanatic
    Automobile(s): 95 STS N* TOTALED
    Join Date
    Feb 2008
    Posts
    244

    Re: 4.6l N* knocks in cold weather, but quiets after operating temp is reached.

    Well, i cant say that myne does it. (never really payed attention tho) Ill listen out for it today. Although, i do alot of WOT's. lol Everyday. I never see carbon fly out of the tips. Even in 1 taking off from a dead stop. Its probly because i dont allow carbon build up. Heavy foot FTW! N* FTMFW!!!


  15. #14
    98eldorado-lee is offline Cadillac Owners Fanatic
    Automobile(s): 1998 eldorado etc
    Join Date
    Nov 2008
    Location
    florida
    Age
    42
    Posts
    176

    Re: 4.6l N* knocks in cold weather, but quiets after operating temp is reached.

    Quote Originally Posted by codewize View Post
    As far as I'm concerned I think a certain amount of knock is pretty normal for these engines in the cold.

    I can assure you I don't have carbon buildup and my car knocks a little in the cold weather until she's warmed up.
    I agree, if it's only for about 30 seconds or so.

  16. #15
    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
    74,524

    Re: 4.6l N* knocks in cold weather, but quiets after operating temp is reached.

    Quote Originally Posted by stoveguyy View Post
    110 sounds like fun but how about just staying in 3rd gear? or even 2nd. that will rev the motor and keep your speed down. its like the joke where the guy got pulled over by a cop and said his alternator was dying so he had to drive fast to keep the motor spinning so the headlights would work. try 2nd gear. duh.
    It's not JUST the high RPM's that clean out the cylinders. It's also the high pressures and temps of WOT and the high engine vacuum on deceleration as well as ring flutter that breaks up any carbon on the rings and keeps them free.

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