Is this normal?
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 11 of 11
Like Tree1Likes
  • 2 Post By NC-V
2004-2007 Cadillac CTS-V Performance Mods Discussion, Is this normal? in Cadillac CTS-V Series Forum - 2004 - 2007; I noticed when coasting down a hill in second gear for about 30 seconds there is almost no engine brake ...
  1. #1
    howanicm is offline Cadillac Owners Fanatic
    Automobile(s): 04 cts v
    Join Date
    Jan 2011
    Location
    Maui Hawaii
    Age
    23
    Posts
    446

    Is this normal?

    I noticed when coasting down a hill in second gear for about 30 seconds there is almost no engine brake and timing is advanced about 36* and throttle position is at 15-17%. After about 30 seconds timing is droped to about 6* and throttle position remains the same. Now there is alot of engine brake. I am still chasing the high idle while coastin in neutral issue and cant for the life of me find a vaccume leak..Im wondering if it is a job for the tuner. Thanks in advanced for the help.

  2. Remove Advertisements
    CadillacForums.com
    Advertisements
     

  3. #2
    PISNUOFF Guest

    Re: Is this normal?

    That is DFCO and completely normal. It does it on flat land also, not only down hills.

    If you're chasing an erratic idle and you didn't change anything to make it change, there is a vacuum leak or a sensor issue. If you've modified things, it needs tuned. There are several parameters that effect it. Which ones to modify depends on what it's doing.

  4. #3
    Twitch's Avatar
    Twitch is offline Cadillac Owners Connoisseur
    Automobile(s): '05 CTS-V, '00 SLS, 98 SLS, 89 Eldo, '80 Eldo
    Join Date
    Mar 2006
    Location
    NYC
    Age
    43
    Posts
    3,992

    Re: Is this normal?

    Yeah, sounds like DFCO to me too. Personally, I disable it below 4th gear. Too jerky if you have a passenger in the car.

    How high is the idle when coasting? It's normal for the idle to hang between 1000-1500 rpm then drop to normal as you come to a stop.

  5. #4
    lollygagger8's Avatar
    lollygagger8 is offline Cadillac Owners Connoisseur
    Automobile(s): Platinum 2004 CTS-V
    Join Date
    Apr 2008
    Location
    Indiana
    Posts
    4,929

    Re: Is this normal?

    36 degrees of advanced timing? Isn't that really high?

  6. #5
    howanicm is offline Cadillac Owners Fanatic
    Automobile(s): 04 cts v
    Join Date
    Jan 2011
    Location
    Maui Hawaii
    Age
    23
    Posts
    446

    Re: Is this normal?

    Pisnuoff- I cant seem to find any vacuume leaks. I sprayed eather around every place that i thought could be leaking. Also if some sensor is bad shouldnt it throw a code? What bad sensors could be causing this type of behaviour? Thanks

    Twithc- It floats up to about 1800 rpm and stays there until i come to a stop. If i downshift on flatground it seems to carry me along there is no engine break unless im not waiting long enough. but then again shouldnt DFCO kick in right away?

    Since i noticed this high idle issue my fuel mileage went from just under 14mpg to about 11.9mpg

  7. #6
    NC-V is offline Cadillac Owners Fanatic
    Automobile(s): '05 CTS-V
    Join Date
    Feb 2010
    Location
    Mooresville, NC
    Posts
    113

    Re: Is this normal?

    howanicm: Like others have said, the "engine braking" you feel kicking in is the DFCO. It will not necessarily kick in right away, there are various parameters that need to be met for it to kick in like: Map values, Throttle position, Speed, Gear selection, Engine temp, etc. So it will kick in sometimes quicker than others depending on your tune/mods.

    Lollygagger: 36* isn't bad, especially under light load cruising or off throttle situations. There are cells in the stock timing tables with ~42+*, LS3s have upwards of 45*.

    Twitch: You may already be aware of this, but you can adjust the ramp in and out rates of the DFCO to "smooth" the engagement and dis-engagement. This makes it a lot more tolerable in lower gears and on the highway. I have it set on my personal V as low as 2nd gear down to 1100 RPMs.
    PISNUOFF and PISNUOFF like this.

  8. #7
    howanicm is offline Cadillac Owners Fanatic
    Automobile(s): 04 cts v
    Join Date
    Jan 2011
    Location
    Maui Hawaii
    Age
    23
    Posts
    446

    Re: Is this normal?

    Ok thanks for all the input guys i appreciate it. I am still new to all the tuning stuff but am trying to learn. Ill try to get you guys a video of whats going on so you can judge the issue for yourselfs.

    Thanks again!

  9. #8
    howanicm is offline Cadillac Owners Fanatic
    Automobile(s): 04 cts v
    Join Date
    Jan 2011
    Location
    Maui Hawaii
    Age
    23
    Posts
    446

    Re: Is this normal?

    I believe Darkman said when you push the clutch in the ecm kills timing, Does anyone know if it also tells the ecm to close the throttle?

  10. #9
    RyRidesMotoX is offline Cadillac Owners Enthusiast
    Automobile(s): 2004 CTS-V Raven, StainlessWorks header back exhaust
    Join Date
    Jul 2012
    Location
    Wildomar, CA
    Age
    29
    Posts
    976

    Re: Is this normal?

    Actually... in all honesty, a video isn't gonna tell most tuners much. Take a log with some tuning software and put it up here. Then we can tell you what's up. I am not a pro ass tuner by any means but I can look at a log and kinda get an idea of what may be wrong.

  11. #10
    howanicm is offline Cadillac Owners Fanatic
    Automobile(s): 04 cts v
    Join Date
    Jan 2011
    Location
    Maui Hawaii
    Age
    23
    Posts
    446
    Should i log,then make the problem happen or can you spot an issue with just a steady driving log? Also, i have a diablosport trinity. I realize these arent real popular around here. Will you be able to read the log i post even tho it was logged with a trinity. Thanks i really appreciate the help!

  12. #11
    RyRidesMotoX is offline Cadillac Owners Enthusiast
    Automobile(s): 2004 CTS-V Raven, StainlessWorks header back exhaust
    Join Date
    Jul 2012
    Location
    Wildomar, CA
    Age
    29
    Posts
    976

    Re: Is this normal?

    I have HP tuners so I can't read your log with the Diablo. I also have never used a Diablo tuner So I don't know what the capabilities are. Maybe someone with more experience with the Diablo can chime in.

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