Stubble on start up

Discussion in 'General Automotive Discussion' started by paul suloff, Sep 26, 2015.

  1. paul suloff

    paul suloff Silver Member

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    Anyone experiencing a stubble or stall on start up? A couple time when I start the car it almost stalls. Like running out of fuel. Never experienced this with a Fuel Injected car. It's like the fuel pump is not up to pressure?
     
  2. hellcat1

    hellcat1 Gold Member

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    Mine runs a little rough in a cold start,, but I just thought it's because it's a huge powerful engine...plus I don't drive it very often
     
  3. TallCool1

    TallCool1 Gold Member Hellcat Car Club Gold Supporting Member Nat'l Hellcat Tech Advisor HCC Charter Member

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    3 or 4 threads on this, no specific root cause (or solution, not quite yet.)

    In my case its not fuel supply. Pressure is there, no decay. Using accessory on to pressure fuel system before start doesn't fix it.
     
  4. Teo

    Teo Judge Yooper

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    Too cold of a plug can cause start problems. Plus we are at 9.5 to 1 CR not the normal 10.9 to 1 like the 392 is. Also a extended tip plug in the 392.

    Mine started hard from day one until warmed up and still continues to do so. I will be checking with NGK for their recommendation here shortly. Backing off one heat range (going hotter) may not be a wise move? Re-gapping to .025 to .028 may help. We are at .031 stock now. Time to play again! :cool:
     
    Last edited: Sep 26, 2015
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  5. Aaron Vogel

    Aaron Vogel Silver Member

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    My car had a little stubble once, I just gave it a shave
     
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  6. Teo

    Teo Judge Yooper

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    Maybe using Nair Hair Off will keep it ------ Gone! :D:p:cool:
     
  7. Aaron Vogel

    Aaron Vogel Silver Member

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    usually just a good waxing
     
  8. Teo

    Teo Judge Yooper

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    :eek::eek::eek::D:p:cool:
     
  9. NorCaletch19He77Kat

    NorCaletch19He77Kat Silver Member

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    Should be ZERO issues with cold start up and plugs will have nothing to do with it unless your car is modified--get to the dealer and they will check MAP, MAF and software for any issues--you should get an initial higher rpm cold start that lasts for about 10 seconds or so--but no stumble or lag issues at all.. These engines are built VERY lean and any data from sensors that cause even leaner fuel conditions will give you the lag, stumble.. Fuel pump problem--I doubt it, because most fuel pump issues are after hot/warmed up run or high rpm demand.. should be very easily corrected at dealer.
     
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  10. redhemi

    redhemi Gold Member

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    On start up mine goes too high idle,at least 1800 rpm,very loud and all the animals run;)then slowly down too a mean rumble :D
     
  11. Lord Hellcat

    Lord Hellcat Gold Member Hellcat Car Club Gold Supporting Member HCC UK President HCC Charter Member

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    Mine does exactly the same. I think you need to take it to your main dealer Paul
     
  12. TallCool1

    TallCool1 Gold Member Hellcat Car Club Gold Supporting Member Nat'l Hellcat Tech Advisor HCC Charter Member

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    It lay very well be bau no cause (which is to say no cure minus tuning) for concern.

    On EFI setups, often tuning correction factors are used, fuel is enriched at cold start. It can be a challenge to optimize combustion during initial cycles while things warm up. It can take a few cycles for MAF to even begin providing useful data, some injector pulses to account for fuel evap etc so lamda targets are adjusted then.

    I'd love to see Hemituner or HighHorseman weigh in on that, they just might be able to educate us, so as to save chasing something that stock tuning may be causing at cold start.

    Tuning is likely different for cold engine starts it would be presumptuous to think it's lean condition related until that's known.
     
    Last edited: Sep 28, 2015
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  13. Lacan

    Lacan Rookie

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    Mine does this every morning. I leave for work early so its colder outside for my area (40 degrees) Ive tripple tapped the start button before starting nothing matters. I've had it to the dealer for P0300 code. They can never find anything wrong since its only at cold start and unable to replicate it. Often I'm told its carbon build up... Sick of the CEL coming on. So now I tripple button start and lightly press the accelerator when the rpms start to drop at start up until it stabilizes itself. Hopefully they find a fix its getting annoying.
     
  14. slester1

    slester1 Silver Member

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    My HC almost stalls also on cold start after sitting for 2 days.
    Rough idle for a few secs then normal but it has done it since day 1 and from all Ive read on here its about normal.

    I don't like it and waiting for a fix like everyone.
     
  15. TallCool1

    TallCool1 Gold Member Hellcat Car Club Gold Supporting Member Nat'l Hellcat Tech Advisor HCC Charter Member

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