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Thread: CAR FIRES UP AFTER 3rd Try.... How to fix

  1. #1
    Tuner in Training
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    CAR FIRES UP AFTER 3rd Try.... How to fix

    This is a 1999 Camaro FI car with a supercharger, stock motor, 2 bar map (readings are now half of what they use to be), and 42 lb green top injectors:

    Car fired up first try when cold before injector correction when cold, but idled at 10.5 AFR, then I modified for injectors and it would not start until I got the cranking ve tables and primary ve tables closer to where I think they should be (added to the values under 1200 RPM)

    Now car fires up holding the throttle down a tad, but on the third try.

    My question is, how do I get it to fire up the first time without having to hold the pedal down?

  2. #2
    Senior Tuner SultanHassanMasTuning's Avatar
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    if you change your injectors and its not scaled properly it will not start right.
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  3. #3
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    Anyone on know the correct scaling for the green top 42 lb injectors? I just added 13 across the board.

  4. #4
    Sent you a PM.

  5. #5
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    Replied to PM, thx!

  6. #6
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    Why would a car fire up after the second or third try consistently? What table can be modified to correct? Injector scaling is right

  7. #7
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    have you run the russ k idle config when cold? Sound like you need more air when cold.

  8. #8
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    I took a look at my OL EQ Ratio and leaned it out for the MAP readings I see at idle. Mine was doing something similar and it was commanding a really rich AFR on startup. Once I commanded a leaner condition, it started firing on the first try. (Mine is happiest around 16:1 at idle) and was previously calling for 11.5:1 for the first few seconds on startup.

    I beat on the airflow tables for a week before looking at fueling as the real culprit. On the bright side, my RAF values are pretty damn close.

  9. #9
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    Quote Originally Posted by 1fstgm View Post
    Why would a car fire up after the second or third try consistently? What table can be modified to correct? Injector scaling is right
    This is nothing to do with your tune if it's correct. GM PCMs don't like to start after getting tunes uploaded. The first or second starts it will die right after cranking over. Usually the 3rd time is a charm. This is from my tuner and seems to be the case. No matter what was uploaded, even a stock file to stock car it would die the first and second start then run fine after the 3rd try.
    Last edited by danieloneil01; 09-24-2013 at 08:46 PM.

  10. #10
    Senior Tuner Ben Charles's Avatar
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    This is nothing to do with your tune if it's correct. GM PCMs don't like to start after getting tunes uploaded. The first or second starts it will die right after cranking over. Usually the 3rd time is a charm. This is from my tuner and seems to be the case. No matter what was uploaded, even a stock file to stock car it would die the first and second start then run fine after the 3rd try.
    Not my experience

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  11. #11
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    You're lucky but it's a known thing. I have uploaded about 50 tunes to my car and 90% of the time it'll die no matter what on the first start. On the 2nd start I might be able to pedal the gas to keep it running for the first 3 seconds then it'll be fine. If not the 3rd try is good to go. After that it will start up every time on the first try.
    Last edited by danieloneil01; 10-01-2013 at 11:23 PM.