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Thread: AFR above 60 KPA goes lean

  1. #1
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    AFR above 60 KPA goes lean

    Hello everyone,

    I have an issue with my Turbo Truck, I have been playing with the tune and the tune file for awhile, thought I was chasing a boost leak, maybe still am? Anyways its a 6.0l Gen 3 P59 computer on a 2 Bar OS. I will add my tune file and Scan file. I have modified this so much since switching from a 3 Bar OS to a 2 bar OS. I feel so lost, this is my first boosted car. I had the truck running well last summer before having some heating issues due to cheap China fan's and other inferior products, which i have tried to change over the winter.

    My main issue is as I drive the truck around, I get these loud back fire issues, which i believe it from it going lean once the RPM start to climb. I cant seem to build any boost on the engine, which i'm not trying to when the AFR's are low. This seems to be a Fuel delivery / air issue. My boost gauge never seems to go positive so i must have a leak somewhere once positive pressure is introduced.

    I have put a smoke machine into the intake, and don't see any smoke until it comes out the turbo filter. Now this isn't pressurized, so some plastic or rubber seal must have failed and is leaking.

    At this point, I'm wondering if I'm looking for a failing fuel pump or a failing fuel regulator, or blown out V Band clamp on my inner cooler?

    Any advise would be great or where to start. I had the truck running well until my water pump went out last year and i had to modify the whole Fan assembly to put larger fans in. It holds coolant, i haven't done a leak down test, but it doesn't seem to burn it or leave the revisor.

    I'm stumped and any advise of how to get this back on the road would be great, thanks in advanced.

    The VE Table isn't tuned as I'm having issues running the motor. I understand the premise of changing the VE Table the the AFR data. First turbo motor, not first tuned car.
    Attached Files Attached Files

  2. #2
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    How are you running this engine?
    open loop SD?
    I see no fuel trims or anting from the O2 sensors

  3. #3
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    Hi Bk2life, I think i may have found an "Not Lose but lose Hose Clamp on my intake boot".

    Open Loop Speed density.

  4. #4
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    So you want to run stoich A/F when in Boost Enrichment? Because that is how you have the BE table set up.

  5. #5
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    Quote Originally Posted by 2xLS1 View Post
    So you want to run stoich A/F when in Boost Enrichment? Because that is how you have the BE table set up.
    Yikes.

  6. #6
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    Aside from the fact that you are not getting any fuel when you give it any throttle, your tune needs a do-over, and you should not be going anywhere near full throttle until you get fuel delivery sorted out anyway. If you were a lot closer to where you should be with fueling you would have already blown the motor. Running too lean to build boost or make any sort of power is saving you right now.

  7. #7
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    FYI, Had my injectors flow tested/ cleaned. Honestly never would have guessed over first winter of having the motor sit. E85 will stick 210's like no other. One almost didn't move this is why my AFR was all over the place. Before and after pictures.... No wonder why everything was such a loss when changing anything. Going back to my tune from last year on the 3 bar.

    This form wont let me attach the photos, but basically, one injector of 5 of the 8 injectors were flowing about 20% of normal.

  8. #8
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    Drag only cars get away with those injectors because they don't care about anything but WOT, and they constantly change parts. They are not even rated for any type of liquid fuel, much less corrosive alcohols. You can find pictures of those injectors that "run just fine" all over the place with rust and various gunk rendering them unusable.

  9. #9
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    Those 210s get stuck after almost no time at all even on straight gasoline, it's not E85 that does it it's those CNG injectors.

    According to HPT, PE/BE will use whichever of those is richer. Setting BE to 1.00 just means it will use the regular PE instead. Assuming the PE isn't also set to 1.00.
    Quote Originally Posted by SiriusC1024 View Post
    I think they're junkyard rebuilds.