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Thread: Strange Restart Problems

  1. #1
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    Strange Restart Problems

    So, I dealt with a very hard start issue from the get go that my original tuner couldn't nail down. From what I could tell (logging cold starts is really hard) it was getting too much fuel and not enough air. I rescaled the injectors to the ID1300 specs, made inj scalar be 16, cut down the startup inj pulsewidth table (I think to about half of stock), and I set the pedal voltage table spot where it had 0.00 volts to be 1.0, essentially opening the throttle without any pedal input. I did that last step because I got the tune to the point it would fire up with pedal input and then stay running fine. I couldn't find a startup airflow table so I went this route.

    After those changes, car fires every single time on cold starts.

    If I park the car after a full warm up cycle and coolant temps sitting around 185*, if I immediately or within 5 min or so with coolant still warm, restart it, it will fire with just a touch of hesitation but it does fire.

    If I wait say 30min or so, the car will turn over one complete start cycle (about 20 seconds) and shows no sign whatsoever of wanting to start. Just cranks and cranks and then stops. EVERY single time though, I hit the starter again after that crank cycle and immediately fires right up, even better than cold starts.

    So I am looking for help on what tables to focus on to help figure this out, its embarrassing to say the least to be at a car show cranking the car like its a 50's gasser.

    I have attached the stock tune, the tune the tuner provided that just wouldn't even start, run, or idle, and my current tune that behaves how I described. Sorry no real logs here, the restart after the long crank interrupts the VCM scanner and so the data is always corrupted.

    2014 Chrysler 300 SRT8 Stock.hpt
    Tuner Tune 1.hpt
    Current Tune_No Cool Restart.hpt

  2. #2
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    Sorry for the full car details:

    Hellion Twin Turbo, Forged 392 (9.5:1 compression), Edelbrock heads, custom cam (230/240, .600 lift, 116+2), 6.1L metal intake manifold, ID 1300 injectors, Triple Fore hat, running 1 450 walbro, 2nd on a hobb switch, 3rd not installed, 10AN feed, 8AN return, boost/vacuum referenced Aeromotive 1000 regulator.

  3. #3
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    Also I have ruled out fuel pressure issues, logged fuel pressure via my pressure sensor and always has full pressure.

  4. #4
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    It?s the fore system. I have to prime my pump after an extended off period.

    Try to place vehicle into run position two times before starting and then fire it up.

  5. #5
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    Quote Originally Posted by 1bh View Post
    It?s the fore system. I have to prime my pump after an extended off period.

    Try to place vehicle into run position two times before starting and then fire it up.
    Thanks, well aware of the Fore "priming" needed, not the issue. I can prime it 12 times on that 30min or so sit time, never fires on the first start cycle.

  6. #6
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    I cant view your files.
    I have a burrito in my colon, yet refried beans come out...
    How i know it's from the same meal? I didn't ingest corn any other time.

  7. #7
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    Beta 3.7 reads, do you have access to beta?

  8. #8
    Doesnt fore have you take the vac multiplier table and populate it with 1s canceling it out?

  9. #9
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    Current tune (not the one posted) has the Vacuum Multiplier set to all 1's, hasn't made any effect to the startup issue.

    On a side note, I tried rescaling the Vacuum Multiplier table so it went as high as 250kpa and left the values all 1's for the multiplier, and the car would fire but not stay running. Found that very strange. Reverted back to stock scaling and all 1 multipliers and went back to normal.

  10. #10
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    Anyone have any suggestions?

  11. #11
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    change the ect sender values for cold start?
    I have a burrito in my colon, yet refried beans come out...
    How i know it's from the same meal? I didn't ingest corn any other time.

  12. #12
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    is it staying in a closed or open loop status?
    I have a burrito in my colon, yet refried beans come out...
    How i know it's from the same meal? I didn't ingest corn any other time.

  13. #13
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    Have it in open loop for now until I get further tuning done on the VE table
    Last edited by 06300CSRT8; 04-28-2018 at 07:11 AM.

  14. #14
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    when it starts up it needs to begin in open loop.
    I have a burrito in my colon, yet refried beans come out...
    How i know it's from the same meal? I didn't ingest corn any other time.

  15. #15
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    Sorry meant I’m forcing open loop right now

  16. #16
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    Any luck getting a handle on this issue?

  17. #17
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    Havent tried the changes yet, track event tomorrow so purely focused on WOT fueling and timing.

  18. #18
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    Did you ever get to the bottom of this? Having the exact same "time related" restart issues.