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Thread: Injector Duty Whilst Cranking 56%!!! WTF!!

  1. #1

    Default Injector Duty Whilst Cranking 56%!!! WTF!!

    HI all,

    Setting up a TT LS1 and had the car starting and idling beautifully on Sat morning, get in this morning and injector duty whilst cranking is hard on 56%, this seems to be related to the map sensor somehow as the engine was SO flooded that no vacuum reading was obtainable, yet if the map sensor is given vacuum manually then the cranking IDC drops back to where it should be.

    Anyone have any ideas?
    Cheers,
    Steve Coates
    http://www.avoturbo.com

  2. #2
    Junior Member DebianDog's Avatar
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    Default Re: Injector Duty Whilst Cranking 56%!!! WTF!!

    Quote Originally Posted by avoturbo
    HI all,

    Setting up a TT LS1 and had the car starting and idling beautifully on Sat morning, get in this morning and injector duty whilst cranking is hard on 56%, this seems to be related to the map sensor somehow as the engine was SO flooded that no vacuum reading was obtainable, yet if the map sensor is given vacuum manually then the cranking IDC drops back to where it should be.

    Anyone have any ideas?
    My friend with a LARGE single on his LS1 says:

    put the fuel maps back

    manifold vaccum during cranking does not change for forced induction

    I have a feeling he threw the maf or the ifr table way off rich maybe trying to get the fuel trims right on whatever injectors he's running
    or maybe he mucked with the fuel system and has way too much fuel pressure

    theres no reason it should crank up any different power adder or no
    2001 Trans-Am - A4 w/2.73
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  3. #3

    Default Re: Injector Duty Whilst Cranking 56%!!! WTF!!

    Quote Originally Posted by DebianDog
    Quote Originally Posted by avoturbo
    HI all,

    Setting up a TT LS1 and had the car starting and idling beautifully on Sat morning, get in this morning and injector duty whilst cranking is hard on 56%, this seems to be related to the map sensor somehow as the engine was SO flooded that no vacuum reading was obtainable, yet if the map sensor is given vacuum manually then the cranking IDC drops back to where it should be.

    Anyone have any ideas?
    My friend with a LARGE single on his LS1 says:

    put the fuel maps back

    manifold vaccum during cranking does not change for forced induction

    I have a feeling he threw the maf or the ifr table way off rich maybe trying to get the fuel trims right on whatever injectors he's running
    or maybe he mucked with the fuel system and has way too much fuel pressure

    theres no reason it should crank up any different power adder or no
    Tried all that, it was working fine on Sat and on Mon had the problem, and it had vacuum on cranking on Sat.

    On Sat it was starting and idling fine. NO changes and Monday morning stuffed..
    Cheers,
    Steve Coates
    http://www.avoturbo.com

  4. #4
    Lifetime Member GMPX's Avatar
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    Apr 2003
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    13,148

    Default

    Just to keep you all updated on this, we have been working with the guys at AVO to sort this car out, it's getting there.

    Cheers,
    Ross

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