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Thread: Suoercharged 03 Silverado 1500 5.3 (LM7)

  1. #11
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    Quote Originally Posted by pinstripebob View Post
    I've been staying with V7.5, but I've looked into switching to V8 recently. You can copy your V7.5 maps to V8 pretty easily. In the V7.5 scan tool, go to your desired map, open its properties, then click the button labeled "Copy for V8."

    Go to your V8 maps, open a map's properties by clicking the little arrow next to "Config" or pressing Shift+F8, then press the clipboard paste button in the top right corner.

    Have you changed your injectors during your installation?
    Hi.

    Yes I changed my injectors. Also updated injector data. But might have done something wrong_ I think Nonnieselman is looking into that to verify my settings. I will try to copy settings from v7.5 to 8.. Or just use 7.5.
    Worked on the car again today. Did not make any progress but verified map sensor and fuel pressure. Old MAP and old tune showed 99.7 to 100.3 kpa while the new MAP was stable at 99 key on engine off.. Not 100%, but should be close enough?
    Bought a 6 bar pressure gauge, but could not find the right adapters to connect it to my fuel rail. So had to disconnect the line from regulator to fuel rail to messure out of the regulator. Goes straight to 56psi when i turn ignition on. Stays there until fuel pump stops and fals back to 0. That is like it should be? Have ordered a 0-100psi/0-5 v transduser to mount in the fuel rail so i can log pressure in the future.

    For those that has not seen my logs and tune, my current problem is that i need values around 100 in the main ve map just to idle at lambda 0. When trying to drive the car the throttle stops working. I can probably increase the etc predicted airflow even more, but the map does not look plausible.
    Last edited by EspenT; July 25th, 2019 at 10:24 AM.

  2. #12
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    Make sure your injector data is correct, you shouldn't need to make changes that large in your VE table. Regarding lambda, do you mean 1 at idle? Are you monitoring AFR from your wide band also, and if so what does it read?

    Fuel pressure should stay high. You might have a faulty fuel pressure regulator, they are a very common fail point on those engines. I had an extremely bad experience with a bad FPR once, replace that thing immediately before you run the engine again. I wouldn't be surprised if you had raw gas coming out your exhaust and gas in your oil if it's anything like a situation I ran into last year.

  3. #13
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    Quote Originally Posted by pinstripebob View Post
    Make sure your injector data is correct, you shouldn't need to make changes that large in your VE table. Regarding lambda, do you mean 1 at idle? Are you monitoring AFR from your wide band also, and if so what does it read?

    Fuel pressure should stay high. You might have a faulty fuel pressure regulator, they are a very common fail point on those engines. I had an extremely bad experience with a bad FPR once, replace that thing immediately before you run the engine again. I wouldn't be surprised if you had raw gas coming out your exhaust and gas in your oil if it's anything like a situation I ran into last year.
    Are you saying that fuel pressure should stay high with ignition on engine off? It goes high when ignition is switched on. Then it goes back down when fuel pump stops after a few seconds. Then it goes back up if you crank. I thought that is like it should be ?

  4. #14
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    Pressure should stay high with the key on and the engine off. I believe you have a manifold-referenced fuel pressure regulator, with a vacuum hose that plugs into your intake manifold (probably right under your blower).

    Take off that hose, turn your key on, and see if fuel comes out of the hose. If fuel comes out, replace the regulator before you do anything else.

    When you were logging, were your fuel trims very different between bank 1 and 2?

    Sent from my Pixel 3 using Tapatalk

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