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Thread: Cos3 01270003 to Cos 5 02020005. Wont start now

  1. #11
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    Quote Originally Posted by 69camaro5speed View Post
    superstepside did you get this fixed if not I may have your fix ?
    I have seen this before, its a easy fix
    No I never did, just stuck with the COS3.

  2. #12
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    SuperStepside: Was curious as to what the potential fix to this was. Was gonna look at doing the exact same thing but not if there's going to be a "not sure" problem with going to cos5.

  3. #13
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    Quote Originally Posted by SuperStepside View Post
    No I never did, just stuck with the COS3.
    Try this adjustments to see if it starts this should help.
    Guessing you have a 2 bar map sensor If not you need to change your scale
    also guessing your injector info is correct

    do a full flash and see how it does

    I have has some where it does not fault the maf meter right away and they will act like that.

    Your setting on MAF Diagnostics could of made it take a while to kick it to sd.

    If you have no maf on the car it will some times not start because its reading the first line of the maf and does not give you enough fuel to start.

    so if you bring up the bottom area of the maf some it gives you more fuel for starting so it can run enough to fault maf and run

    I Have seen this many times even with maf setting to 1 some times they will not start ....
    Attached Files Attached Files

  4. #14
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    Quote Originally Posted by MurderMitten View Post
    SuperStepside: Was curious as to what the potential fix to this was. Was gonna look at doing the exact same thing but not if there's going to be a "not sure" problem with going to cos5.
    Murdermitten co 5 works great I have used it 1xx times na ,boosted and nos cars It rocks

  5. #15
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    Quote Originally Posted by 69camaro5speed View Post
    Try this adjustments to see if it starts this should help.
    Guessing you have a 2 bar map sensor If not you need to change your scale
    also guessing your injector info is correct

    do a full flash and see how it does

    I have has some where it does not fault the maf meter right away and they will act like that.

    Your setting on MAF Diagnostics could of made it take a while to kick it to sd.

    If you have no maf on the car it will some times not start because its reading the first line of the maf and does not give you enough fuel to start.

    so if you bring up the bottom area of the maf some it gives you more fuel for starting so it can run enough to fault maf and run

    I Have seen this many times even with maf setting to 1 some times they will not start ....
    Still havent gotten around to trying cos 5 again. Yea I made sure that the tables were the same between the cos3 and 5. Running speed density. Ill have to try this when I get the chance. Thanks for the help.

  6. #16
    Joe (Moderator) joecar's Avatar
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    Quote Originally Posted by 69camaro5speed View Post
    ...

    If you have no maf on the car it will some times not start because its reading the first line of the maf and does not give you enough fuel to start.

    so if you bring up the bottom area of the maf some it gives you more fuel for starting so it can run enough to fault maf and run

    I Have seen this many times even with maf setting to 1 some times they will not start ....
    That's a good trick to know

  7. #17
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    Quote Originally Posted by joecar View Post
    That's a good trick to know
    This is because it is not setting up the code for the Mass Air. All these cars crank in SD. If your P010x doesn't set quick enough this will happen.
    "All that is needed for the triumph of evil is that good men do nothing..."

  8. #18
    Joe (Moderator) joecar's Avatar
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    Yes, without a MAF DTC the ECM reads the MAF, so bringing up the MAF low cells gives you more fuel to allow starting.

  9. #19
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    Quote Originally Posted by joecar View Post
    Yes, without a MAF DTC the ECM reads the MAF, so bringing up the MAF low cells gives you more fuel to allow starting.
    That is what I seen on the 03 04 stuff a lot i have done a lot of off road buggys where they shut the master power off all the time so this help when dfc gets reset every time other wise you some times (depending on couple things) will pull your hair out working on them

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