Page 2 of 3 FirstFirst 123 LastLast
Results 11 to 20 of 26

Thread: somewhat sluggish at times

  1. #11
    Lifetime Member Mitco39's Avatar
    Join Date
    Jan 2009
    Posts
    648

    Default

    Is your EGR blocked? Your maf is still reading low in that first screen which is limiting your fuel (and thus your power) if your EGR is intact but turned off chances are the valve is sticking open slightly and its sucking in exhaust gasses instead of fresh air.

  2. #12
    Lifetime Member LB72004's Avatar
    Join Date
    Dec 2011
    Posts
    292

    Default

    it is turned off but i doubt it is blocked. i looked and didn't see anything that looked like a blocker plate.

    i take it this will be my next step. get a blocker plate in there and run another log?
    2008 Chevrolet 3500HD DRW LTZ
    285/75/17 Nitto Dura Grapplers, 4.56 gears, Front and rear ARB lockers, Efi Live tuning by me, Raptor 160 LP, Cognito 4-6 NTB Lift, 4" Exhaust, Built Trans by Mike L.

    Sold - 2004 LB7 Duramax, EFI Live with DSP5 Tune
    stage 4 SC transmission, 265/70/16 tires

  3. #13
    Lifetime Member Mitco39's Avatar
    Join Date
    Jan 2009
    Posts
    648

    Default

    I would put money on it that that will solve your issue. Its typical to see it stick open sometimes and closed others.

  4. #14
    Lifetime Member LB72004's Avatar
    Join Date
    Dec 2011
    Posts
    292

    Default

    ok, ill put $10 down. you?
    2008 Chevrolet 3500HD DRW LTZ
    285/75/17 Nitto Dura Grapplers, 4.56 gears, Front and rear ARB lockers, Efi Live tuning by me, Raptor 160 LP, Cognito 4-6 NTB Lift, 4" Exhaust, Built Trans by Mike L.

    Sold - 2004 LB7 Duramax, EFI Live with DSP5 Tune
    stage 4 SC transmission, 265/70/16 tires

  5. #15
    Lifetime Member Mitco39's Avatar
    Join Date
    Jan 2009
    Posts
    648

    Default

    You would put money against the fact that its your EGR? lol

  6. #16
    Lifetime Member LB72004's Avatar
    Join Date
    Dec 2011
    Posts
    292

    Default

    i was thinking there was a small chance i could win something here

    if not then you win $10 for helping me out
    2008 Chevrolet 3500HD DRW LTZ
    285/75/17 Nitto Dura Grapplers, 4.56 gears, Front and rear ARB lockers, Efi Live tuning by me, Raptor 160 LP, Cognito 4-6 NTB Lift, 4" Exhaust, Built Trans by Mike L.

    Sold - 2004 LB7 Duramax, EFI Live with DSP5 Tune
    stage 4 SC transmission, 265/70/16 tires

  7. #17
    Lifetime Member Mitco39's Avatar
    Join Date
    Jan 2009
    Posts
    648

    Default

    It was more a figure of speech. I am not interested. Use the money you might have to send to me to pay for your plate and call it a day.

  8. #18
    Lifetime Member LB72004's Avatar
    Join Date
    Dec 2011
    Posts
    292

    Default

    i know, i was just joking with you to see how interested you actually were.

    thanks for your help so far. i will work on get it blocked off and post a new log
    2008 Chevrolet 3500HD DRW LTZ
    285/75/17 Nitto Dura Grapplers, 4.56 gears, Front and rear ARB lockers, Efi Live tuning by me, Raptor 160 LP, Cognito 4-6 NTB Lift, 4" Exhaust, Built Trans by Mike L.

    Sold - 2004 LB7 Duramax, EFI Live with DSP5 Tune
    stage 4 SC transmission, 265/70/16 tires

  9. #19
    Lifetime Member LB72004's Avatar
    Join Date
    Dec 2011
    Posts
    292

    Default

    so i think you have convinced me that it is a leaking EGR. i was able to take it out on a run earlier today and hold the throttle steady with a long enough road and not let off. it did the same thing acting sluggish and smoking for about 5 seconds and then all of a sudden the exhaust cleaned up and started accelerating quickly.

    with your explanation above and this, i am thinking that the vanes being closed trying to make boost is creating high drive pressure. this forces the EGR open and exhaust replaces air and causes the smoking. after a bit the boost raises to a point that the vanes open up enough that the drive pressure no longer holds the EGR open. with only air and no exhaust going into the intake the fuel burns better and the engine makes more HP. also when the EGR closes and the exhaust stops replacing the air then the grams/sec go up and this is when the ECM can now add more fuel

    does this sound right?

    i have order a blocker plate and will put it on when it gets here and will run the test again and see if it is all good
    2008 Chevrolet 3500HD DRW LTZ
    285/75/17 Nitto Dura Grapplers, 4.56 gears, Front and rear ARB lockers, Efi Live tuning by me, Raptor 160 LP, Cognito 4-6 NTB Lift, 4" Exhaust, Built Trans by Mike L.

    Sold - 2004 LB7 Duramax, EFI Live with DSP5 Tune
    stage 4 SC transmission, 265/70/16 tires

  10. #20
    Lifetime Member Mitco39's Avatar
    Join Date
    Jan 2009
    Posts
    648

    Default

    Yes that sounds correct. Have you increased your maximum vane position tables over stock by much? IIRC it shouldnt allow them to sit that closed because of that very reason, you want to keep your drive pressure under control.

Page 2 of 3 FirstFirst 123 LastLast

Similar Threads

  1. Sluggish Truck
    By Chuckels in forum Duramax LB7
    Replies: 2
    Last Post: September 17th, 2012, 11:12 PM
  2. 4l80 shifting sluggish and not shiting at wot
    By Cool28 in forum 4speed RWD/FWD Transmission Tuning (incl T42)
    Replies: 3
    Last Post: March 15th, 2012, 09:49 AM
  3. Car feels sluggish after MAF removal
    By Alex99 in forum Gen III V8 Specific
    Replies: 3
    Last Post: August 18th, 2009, 03:36 AM
  4. Stock 4L65E sluggish 1-2 shift at light throttle - Dashboard attached
    By pacer265 in forum 4speed RWD/FWD Transmission Tuning (incl T42)
    Replies: 0
    Last Post: July 12th, 2008, 05:25 PM
  5. Truck feels sluggish at part throttle
    By Aint Skeered in forum General (Petrol, Gas, Ethanol)
    Replies: 0
    Last Post: June 9th, 2007, 04:52 AM

Posting Permissions

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