Page 1 of 2 12 LastLast
Results 1 to 10 of 13

Thread: Feature request, custom control over fuel transfer pump relay

Hybrid View

Previous Post Previous Post   Next Post Next Post
  1. #1
    New Member
    Join Date
    Dec 2014
    Posts
    9

    Default Feature request, custom control over fuel transfer pump relay

    Request to the EFILive guys (or anyone else who can suggest a better way). I just installed a lift pump on the truck. When I was figuring out my wiring I realized I had a "spare" relay in the stock underhood box labeled fuel pump. Turns out this is for the transfer pump if you have dual tanks. I don't so I figured I'd use the same relay. Already fused, even has "prime" contact in the box so you can manually jumper a wire to run the pump for priming.

    It is factory wired to the ECU and from EFILive I can trigger a DVT to turn the pump on and off. I tried playing with the fuel settings but could not find a way to get the system to normally turn it on.

    The custom digital output with the DSP will allow me to use that digital and swap pins but I'd rather directly use the one already wired (plus I have the other free for future playing). Also most of the input changes are not helpful. Ideal behavior would be:
    • Key-on, prime for 2 seconds and then turn off.
    • Engine running, pump on.
    • Engine stops, pump off.


    Any mechanism to get this feature added or any suggestions on how to control the ECU pin another way? Would be handy for everyone adding a lift pump who does not have a dual tank setup (many of us). Really nice to have all the relays and fuses in stock locations if possible.

  2. #2
    Lifetime Member GMPX's Avatar
    Join Date
    Apr 2003
    Posts
    13,148

    Default

    Sorry, we won't be doing any modifications to the DSP OS's for this ECM.
    I no longer monitor the forum, please either post your question or create a support ticket.

  3. #3
    Lifetime Member THEFERMANATOR's Avatar
    Join Date
    Mar 2009
    Posts
    800

    Default

    Quote Originally Posted by GMPX View Post
    Sorry, we won't be doing any modifications to the DSP OS's for this ECM.
    It's not a change to the DSP OS as ALL the DURAMAX ECM's have this capability. ALL DURAMAX's could have came with dual tanks, and have the circuitry and wiring there for a transfer pump. GM used this setup in the vans with a DURAMAX under the hood, so the architecture is there and proven to work. I know if we had this feature, MANY would use it to control there lift pumps. The DSP output is the one he was talking about that dealt with the DSP OS. Since mine is an early engine, I use the 3 wire GM oil pressure switch(but I don't have the prime feature).
    1995 GMC 2500 SUBURBAN powered by 01 DURAMAX/ALLISON, little of this, a little of that,
    DIAMONDEYE 4" exhaust, CORSA muffler, AFE stage 1 dry filter, custom tuning by me, KENNEDY single pump and pump rub kit.

  4. #4
    New Member
    Join Date
    Jan 2015
    Posts
    9

    Default

    Even though the fuel system segments show a different part number

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

    Default

    Thanks for the reply. If you guys ever decide to dust this OS off and add this (or help support a one off mod) let me know.

  6. #6
    Lifetime Member GMPX's Avatar
    Join Date
    Apr 2003
    Posts
    13,148

    Default

    Just so you don't sit there forever waiting, it will probably never happen, sorry.
    I no longer monitor the forum, please either post your question or create a support ticket.

  7. #7
    Junior Member
    Join Date
    Jul 2013
    Posts
    12

    Default

    Quote Originally Posted by GMPX View Post
    Just so you don't sit there forever waiting, it will probably never happen, sorry.
    too bad, really would be the right way to get it done.
    04 LLY Crew cab
    Complete LBZ intake
    EGR is gone
    PCV delete
    resonator delete
    EFI Live DSP5

  8. #8
    Lifetime Member dansdieselp's Avatar
    Join Date
    Apr 2009
    Posts
    606

    Default

    Fuse tap Ignition Fuse and close the hood.
    Dan's Diesel Performance
    www.dansdieselperformance.com

  9. #9
    New Member
    Join Date
    Jan 2015
    Posts
    9

    Default

    What year and operating system is your truck

  10. #10
    New Member
    Join Date
    Jan 2015
    Posts
    9

    Default

    After pulling up my fuel system the pid is there for the secondary sender. I wonder if you adjusted the total tank size and set the secondary sending unit up if it would control the transfer pump

Page 1 of 2 12 LastLast

Similar Threads

  1. Bad ECU? Trailblazer SS, only 5.7 volts at fuel pump relay
    By Praxis in forum Gen IV V8 Specific
    Replies: 5
    Last Post: October 1st, 2014, 11:32 AM
  2. Using the AC relay output to control a second fuel pump
    By ttls1 in forum Gen IV V8 Specific
    Replies: 2
    Last Post: December 31st, 2013, 10:13 PM
  3. fuel pump control
    By THEFERMANATOR in forum Duramax LB7
    Replies: 6
    Last Post: August 9th, 2013, 05:13 AM
  4. fuel pump relay constantly switching
    By steve40 in forum Gen III V8 Specific
    Replies: 1
    Last Post: July 3rd, 2009, 01:32 PM
  5. Custom OS 3 Bar fuel control questions!
    By Redline Motorsports in forum General (Petrol, Gas, Ethanol)
    Replies: 11
    Last Post: December 1st, 2005, 10:47 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
  •