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Thread: cold start and warm up is terrible.

  1. #1
    Fuel Injected!
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    Mar 2012
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    cold start and warm up is terrible.

    So I tuned my system when the weather was nice. But now we are sub-0c. I started her up and she was rough, really rough. Normally I can druve her away and she is warm in a few minutes. Last night however, I had to gingerly drive her several minutes. I couldn't accelerate reasonably, and when I tried, I'd here a popping life a muffled champagne cork. (Like a pop through a narrow opening (a valve?) So it came out kinda like a shhhhht) these pops stall the vehicle.

    I'm wondering what is different aside from target RPM? Is timing advanced, retarded? Do I need to add more fuel? If so what table?

    I'm using a 16197427.
    I have a cam (isky 262) and an alum. intake.
    Last edited by Scorp1us; 11-22-2014 at 05:51 AM.

  2. #2
    Fuel Injected! 1BadAction's Avatar
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    Limit the cold start spark adders (around 20% of what is there originally) if you're running more compression and see where you end up... Originally these TBI engines were such low compression they needed a TON of spark and fuel on a cold start. If you're still the same compression, you may need to add more fuel (popping through intake) or less fuel (popping through exhaust).
    2010 Porsche Cayenne GTS - DD
    1991 2500 Suburban - 454ci BBC tow monster
    1979 16' Action Marine/"Johnny Cash" Merc Bridgeport Champ Motor - Metalflake Maniac

  3. #3
    Fuel Injected!
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    Thanks. I'm higher compression too. I forgot I had got it decked when I wrote that.

    Also, dumb question... but... if my blms are 128 open loop (stoich), is a value of 120 in a cell richer or leaner than soich? I'm not talkng the adjustment, I'm talking about if that value will put more or less fuel in than 128?

  4. #4
    Fuel Injected! 1BadAction's Avatar
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    It's trying to add less fuel at 120, but BLMs in open loop are always 128 because they are disabled. When it goes into closed loop is when the ECM starts to correct, hence the 120 number (trying to take away fuel).
    2010 Porsche Cayenne GTS - DD
    1991 2500 Suburban - 454ci BBC tow monster
    1979 16' Action Marine/"Johnny Cash" Merc Bridgeport Champ Motor - Metalflake Maniac

  5. #5
    Fuel Injected!
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    59
    I modified my CTS something or another Map and Temp table to 20‰ and that worked! Thanks so much!

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