Page 1 of 2 12 LastLast
Results 1 to 10 of 12

Thread: Possible boost leak

  1. #1
    New Member
    Join Date
    Jun 2014
    Posts
    9

    Default Possible boost leak

    Could somebody please review this log for anything obvious. I am getting 9 MPG towing #13000 fifth wheel. No smoke, no engine codes just horrible mileage. 60mph-70mph towing in 5th or 6th doesn
    Attached Files Attached Files

  2. #2
    Junior Member
    Join Date
    Nov 2018
    Posts
    19

    Default

    What file app can I get to open these files on iphone

  3. #3
    Lifetime Member
    Join Date
    Mar 2006
    Posts
    4,935

    Default

    Quote Originally Posted by Tommy ashley View Post
    What file app can I get to open these files on iphone
    None, EFILive is Windows only. You can do some minor switching of DSP tunes on certain applications on Android only.
    ~Erik~
    2013 Sonic RS Manual - 1.4L I4T E78, tuned, turbo mods, etc.
    2008 TrailBlazer SS 3SS AWD Summit White - LS2 E67/T42, bolt ons, suspension, etc.
    2002 Chevy TrailBlazer LT 4X4 Summit White - 4.2L I6 P10, lifted, wheels, etc.

  4. #4
    Lifetime Member GMC-2002-Dmax's Avatar
    Join Date
    Dec 2005
    Posts
    1,294

    Default

    Quote Originally Posted by mkinnunen View Post
    Could somebody please review this log for anything obvious. I am getting 9 MPG towing #13000 fifth wheel. No smoke, no engine codes just horrible mileage. 60mph-70mph towing in 5th or 6th doesn
    That is expected mileage towing depending on speed and shape/type of trailer.

    9-12 mpg is all you can expect towing that weight.
    www.mscservices.net


    Tuner of many, many Duramax and Cummins Diesels.


  5. #5
    New Member
    Join Date
    Jun 2014
    Posts
    9

    Default

    I would like 12 MPG, since i can expect that, what should i do to improve what i am getting?

  6. #6
    Lifetime Member GMC-2002-Dmax's Avatar
    Join Date
    Dec 2005
    Posts
    1,294

    Default

    Quote Originally Posted by mkinnunen View Post
    I would like 12 MPG, since i can expect that, what should i do to improve what i am getting?
    Driver slower, speed kills MPG, just because you expect or want a given fuel mileage does not mean you can have it.

    Trailer design, towing while a head wind fights you, towing grades.........be happy its not a gasser.

    I have had a Duramax since 2002, the best I got towing my 10K 24/ft V-Nose was 11.6, it got as bad as 9.9 in certain conditions.

    Keep it at 62-65 mph, anything over that..........kiss fuel mileage BYE, BYE
    www.mscservices.net


    Tuner of many, many Duramax and Cummins Diesels.


  7. #7
    New Member
    Join Date
    Jun 2014
    Posts
    9

    Default

    But even at 60, I get 9 mpg, so again your "advise" of keeping between 62-65 holds no new usable information, My gasser gets 6-9 mpg pulling the same trailer. Someday i'll find what is the issue and i will report back, or if after all the tuning options have been explored and all the hard parts have been replaced i'll concede that my truck just gets 9 mpg and it is what it is.

    Thanks everybody for your input.

  8. #8
    Member
    Join Date
    Feb 2016
    Posts
    62

    Default

    Looking at the log, it seems you have low air flow across your MAF for some reason. You have a max of 47.83 lb/min at 3229 RPM. Should be 60+ lb/min from my personal experience. The boost is following desired within about 1psi. Not sure why your vanes are closed so much most of the time. It's averaging over 70% throughout the log. Is this a tune you are working on yourself?

  9. #9
    New Member
    Join Date
    Jun 2014
    Posts
    9

    Default

    Bdirtymax, thank you for reviewing the log, yes I am working on this tune myself, the only changes from stock at the time of that log was EGR block and speedometer adjustment although I have made many changes since then. I also was concerned about the MAF flow (in a different thread), Cleaned it and had the opportunity to travel to phoenix where the flow seemed normal (about 20% difference) so I believe The low MAF is from elevation (5500ft). I had only checked MAF flow at idle, that may have been a mistake.

    Thank you,
    Michael

  10. #10
    Member
    Join Date
    Feb 2016
    Posts
    62

    Default

    Quote Originally Posted by mkinnunen View Post
    Bdirtymax, thank you for reviewing the log, yes I am working on this tune myself, the only changes from stock at the time of that log was EGR block and speedometer adjustment although I have made many changes since then. I also was concerned about the MAF flow (in a different thread), Cleaned it and had the opportunity to travel to phoenix where the flow seemed normal (about 20% difference) so I believe The low MAF is from elevation (5500ft). I had only checked MAF flow at idle, that may have been a mistake.

    Thank you,
    Michael
    Yes the higher altitude would affect your MAF readings. Without seeing more tune data (more pids) or the tune itself it could be anything. It is still odd that it is commanding such high vane position all the time, even high altitude tables don't run that high. The base transient table runs higher but not the entire table. I don't know if this is a single tune or dsp tune either. Fuel pressure looks ok but it could be timing, pulse or combination of.

Page 1 of 2 12 LastLast

Similar Threads

  1. IFR boost/non boost
    By Harrismarine in forum Gen III V8 Specific
    Replies: 4
    Last Post: September 3rd, 2012, 01:59 PM
  2. will a small exhaust leak change my wideband readings a lot?
    By ryans1000 in forum General (Petrol, Gas, Ethanol)
    Replies: 3
    Last Post: November 2nd, 2009, 01:59 PM
  3. Boost leak MAF Reading
    By lownslo in forum Gen III V8 Specific
    Replies: 6
    Last Post: October 16th, 2009, 12:40 PM
  4. Use MAF for off boost/2 Bar SD when in boost
    By Earl H in forum Forced Induction and Nitrous Oxide (N20)
    Replies: 26
    Last Post: May 24th, 2007, 11:58 AM
  5. Idle issues after fixing MAP sensor leak!!!
    By Darkness in forum General (Petrol, Gas, Ethanol)
    Replies: 3
    Last Post: July 31st, 2006, 12:56 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
  •