Author Topic: Hard starting when cold  (Read 506 times)

marcelmot

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Hard starting when cold
« on: Mar 13, 2021, 11:41:37 am »
Hello,

A friend of mine owns a 09 Raider and has some issues at cold starting. Battery & plugs are new and all is stock.
Basically there are two symptoms :
1. The engine has to spin a long time before starting.
2. After starting, the engine runs for few seconds then stops.

When hot, it is fine, none of the above symptoms occur.

Thinking about the fuel pump ? or the ISC to check ?

Thanks for help.
Marcel
My life it's an endless fight against maturity.
"You have your way. I have my way. As for the right way, the correct way, and the only way, it does not exist."

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    ROADKILL

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    Re: Hard starting when cold
    « Reply #1 on: Mar 13, 2021, 12:08:00 pm »
    From your comment looks like you are on the right track

    Ares X

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    Re: Hard starting when cold
    « Reply #2 on: Mar 13, 2021, 07:25:04 pm »
    I tended to only have stalls with the fuel pump when the tank was low, which for me tended to be in afternoons since I always filled up after work on the way home. 

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      Alan

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      Re: Hard starting when cold
      « Reply #3 on: Mar 17, 2021, 08:13:00 pm »
      I am having a hard time starting after adding a BAK. I have to give it gas and rev it for a while to get it warm first then, no problems. What is the ISC?

      marcelmot

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      Re: Hard starting when cold
      « Reply #4 on: Mar 18, 2021, 02:36:08 am »
      Idle Speed Control and it controls the idle.
      Is located just behind the frame neck, think you have to remove also the tank to get to it.
      My life it's an endless fight against maturity.
      "You have your way. I have my way. As for the right way, the correct way, and the only way, it does not exist."

      the urban legend

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      Re: Hard starting when cold
      « Reply #5 on: Mar 18, 2021, 06:17:40 am »
      Idle Speed Control and it controls the idle.
      Is located just behind the frame neck, think you have to remove also the tank to get to it.

      No you remove it from underneath.
      I'd rather die on a motorcycle than live without one.

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      Alan

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      Re: Hard starting when cold
      « Reply #6 on: Mar 20, 2021, 09:05:21 am »
      well it idles fine after its warm. I will check it out thanks! Maybe i moved it when i did the bAK?

      Alan

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      Re: Hard starting when cold
      « Reply #7 on: Mar 20, 2021, 09:17:12 am »
      now that i think about it, i believe its mounted under the tank now. I will have to take the tank off i guess and replug it in or test it somehow

      the urban legend

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      Re: Hard starting when cold
      « Reply #8 on: Mar 20, 2021, 10:43:52 am »
      well it idles fine after its warm. I will check it out thanks! Maybe i moved it when i did the bAK?

      The ISC takes air from a fairly large hose connected to the front of the stock air box, and distributes a controlled amount to each throttle body via 2 smaller hoses. If you plugged that large hose when you did the BAK, that would definitely cause a problem.
      I'd rather die on a motorcycle than live without one.

      ,,

      Alan

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      Re: Hard starting when cold
      « Reply #9 on: Mar 20, 2021, 08:23:42 pm »
      well i would not have plugged it. Is the ISC different than the two oxygen sensors? I have them relocated on the plate under the tank as i remember,

      the urban legend

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      Re: Hard starting when cold
      « Reply #10 on: Mar 21, 2021, 04:48:47 pm »
      well i would not have plugged it. Is the ISC different than the two oxygen sensors? I have them relocated on the plate under the tank as i remember,

      There's only one oxygen sensor, and it's on the exhaust pipe. You're probably referring to the 2 MAP (manifold absolute pressure) sensors.
      Obviously the use of incorrect terminology will make helping you a bit more complicated.

      The ISC (idle speed control) unit is an electrically powered step motor that controls the amount of air that enters the throttle bodies when the throttle is closed (idle). Normally you hear it reset into the fully open position when you shut the engine off. It makes a kind of whirring sound. It's located in the neck of the frame, and has 3 hoses connected to the bottom: one large hose from the stock air cleaner box, and 2 smaller hoses going to each throttle body. If it's stuck in an almost closed position (or the big hose is plugged), the engine could still get enough air to idle correctly when hot, but would lack the "fast idle" capacities needed to start or run properly when cold.
      I'd rather die on a motorcycle than live without one.

      ,,