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Thread: Does anyone know the RS6 fuel pressure at the fuel rail?

  1. #1
    Registered User TozoM8's Avatar
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    Does anyone know the RS6 fuel pressure at the fuel rail?

    For some reason my car looses it's power above 5K rpm. It misses, but no fault codes. Boost is at 6-7lbs air-fuel ratio at 13.5. It just started to do it a couple days ago. If I get on it, it pulls great for a couple second then start cutting out. Maybe my fuel pump is going.
    05 Cayenne turbo

  2. #2
    Registered User hahnmgh63's Avatar
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    Tozo, you could run some Vag logs since there are no fault codes as of yet. You can run the Advanced measuring blocks and check for misfires, group 115 in basic measuring for boost, 20 & 21 are all cylinders knock sensors. There are many measuring blocks in basic & advanced you can check. At least get some basic stuff logged to start checking then throw some logs our way and from them we might be able to determine what's up.
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  3. #3
    Registered User TozoM8's Avatar
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    This is on my S8 so no boost or EGT reading by ECU.
    05 Cayenne turbo

  4. #4
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    How do you know A/F is 13/1?

    You can log O2 sensors and report the voltage.

    Sounds like fuel is going lean under boost. You will feel the car "bucking" under boost if too lean. May or may not throw a code.


    \
    Quote Originally Posted by TozoM8 View Post
    This is on my S8 so no boost or EGT reading by ECU.

  5. #5
    Registered User TozoM8's Avatar
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    I have an air/fuel ratio gauge. It is wired to the DS O2 sensor.
    Idle http://audipages.com/tozo/10%20lbs%20vacuum.JPG
    5-6lbs http://audipages.com/tozo/6lbs%20boost.JPG
    05 Cayenne turbo

  6. #6
    Registered User marklar182's Avatar
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    Elsa says;

    3.5 bar with FPR vacuum line attached at idle
    4.0 bar with FPR vacuum line removed at idle
    2008 A4 2.0TQ Quartz Grey Metallic S-Line/Titanium Package
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  7. #7
    Registered User TozoM8's Avatar
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    Thanks! I will look into it this weekend.
    05 Cayenne turbo

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