Rough running 95" with P0108 code

Discussion in 'Engine, Fuel and Exhaust' started by Denco09, Dec 2, 2009.

  1. Denco09

    Denco09 New Member

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    Can't find mid range stumble. Have changed TPS and MAP sensor. Problem seems to be worsening. Recent engine rebuild with Screaming Eagle 95", MC Gerolomy Heads, stage II Screaming cams, Thunder Header and Power Commander. Have played with different mapping but still stumbles and seems to be starting to pop at low end. What would set a PO108 code other than sensor failure?
     
  2. Hoople

    Hoople Account Removed

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    How soon after you clear the P0108 (map High) code will the ECM reset another P0108. Is the Power Commander you have only in series with the 2 injectors & subs just the o2 sensors?

    You also could try to force the Map input to the ECM, "low", to see if the ECM will respond to a P0107 (map low/open). If it responds, it does indicate the ECM channel is Good.

    I don't know if map Low is "Go-Rich" or "Go-Lean" in your case, but when you force the map low, (because right now the ECM thinks the map is HI) the bike should show a dramatic change (good or bad) in the way it runs.
     
  3. glider

    glider Veteran Member

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    Have you checked the obvious like intake leaks?
     
  4. Hoople

    Hoople Account Removed

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    Wow, so true. I was not thinking.. Do what Glider says first.

    Then Rip the Bike Apart!! :p
     
  5. Drumrguy

    Drumrguy Account Removed

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    If you find no leaks, if you just downloaded a map, you should be able to call the fuel management company and have them send you a better map for your bike, also if you got head work, bike has to go on the dyno to be tuned, these fuel management companies tell me their prebuilt maps do not work on motors with extensive work like heads, I know, I went through this also, I had no codes though.