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Thread: Gen IV initial start up no fuel

  1. #1
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    Gen IV initial start up no fuel

    Good afternoon, first post here looking for some direction.

    2007 Escalade 6.2 w/6L80E, standalone OEM harness, OEM computer.

    Sitting in a frame which will receive a 1949 Suburban.

    Engine turns over with the key switch, the fuel pump cycles while cranking (test light confirmed), there is fuel flowing through the rails (tested at Schrader valve), VATS is disabled with HP Tuners, injectors are not firing (no start plus tested with a Noid), injector fuse is good, ignition relay tested good (confirmed power and ground), P0615 starter relay and U0100 lost communication with ECM codes.

    I'm not sure where to look next for the loss of power to the injectors.

  2. #2
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    No power "loss of power" to the injectors or no control of the injectors via ground at the ecm?

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    The ECM itself is grounded, I started testing harness grounds (I'll finish tomorrow as I ran out of energy). There aren't that many in the harness, 3 that I recall. Battery, engine and chassis grounds are all battery direct.

  4. #4
    Tuning Addict edcmat-l1's Avatar
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    WTF with all the posts asking for help with no data logs or tune files. No one can do anything but guess.

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  5. #5
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    Quote Originally Posted by Mike Correll View Post
    The ECM itself is grounded, I started testing harness grounds (I'll finish tomorrow as I ran out of energy). There aren't that many in the harness, 3 that I recall. Battery, engine and chassis grounds are all battery direct.
    Not sure what "the ECM is grounded" means. Do you have +12v at the injector and is the ecm grounding them to turn them on.

  6. #6
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    Quote Originally Posted by edcmat-l1 View Post
    WTF with all the posts asking for help with no data logs or tune files. No one can do anything but guess.
    And they all use very imprecise language on the problem. You not only have to guess at a solution, you have to guess at what their real problem is.

    Is it that time of the year were all of the winter projects are getting wrapped up? How many no start swap questions came through yesterday.

  7. #7
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    Everyone isn't fluent with this stuff. A little guidance his a long way.

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    Just to be sure I confirmed that wherever the ground signal comes for the ecm is indeed grounded.

    I checked the injector plugs and I have power and ground. This led me to believe it is something to do with what I did with vats. In the end I wasn't writing the entire modified file to the ecm. I click on very little at this point as to not mess anything up. It starts now.

  9. #9
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    Quote Originally Posted by Mike Correll View Post
    Everyone isn't fluent with this stuff. A little guidance his a long way.
    Hard to impossible to remote trouble shoot electrical without knowing the level of the onsite troubleshooter. At this point, it sounds like you think the ecm is supposed to supply +12v to the injectors to control them. They receive full time +12v from the fuse panel and the ECM grounds them for control.

    Do you have the wiring diagrams for you donor vehicle?
    Last edited by gtstorey; 2 Weeks Ago at 01:51 PM.

  10. #10
    Quote Originally Posted by Mike Correll View Post
    Just to be sure I confirmed that wherever the ground signal comes for the ecm is indeed grounded.

    I checked the injector plugs and I have power and ground. This led me to believe it is something to do with what I did with vats. In the end I wasn't writing the entire modified file to the ecm. I click on very little at this point as to not mess anything up. It starts now.
    Mike

    I had a similar problem. Turned out to be a bad ground connector in the crank sensor. No trouble codes were thrown. I'd check all your sensors

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