tech help please

Discussion in 'Touring Models' started by alant123, Sep 28, 2008.

  1. alant123

    alant123 New Member

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    Hi, I have just purchased a 2001 FLHTCUI and it backfires very badly when the throttle is shut down, I think the injectors want resetting, it has been fitted with different mufflers. Would you think this is the case?
    thanks
     
  2. glider

    glider Veteran Member

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    There's no such thing as resetting the injectors. Different fuel delivery is possible with a tuner. Have you tried some injector cleaner like gumout in the fuel?

    Your problem as I understand it is it pops on deceleration?

    If so, check for any leaks in the exhaust system. Other than the popping, how does it run. Need more input here.
     
  3. TQuentin1

    TQuentin1 Well-Known Member Staff Member Moderator

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    Alan,

    As Glider mentioned, check for exhaust leaks. You can do this when you first start up the bike by CAREFULLY running your hand along the pipes but NOT touching the metal. Pay particular attention to the junctions where there are clamps connecting the two. You should feel any leaks. I have an '03 UC and there was a crack on the rear crossover pipe right at the welded junction where the pipe splits to go left and right. This crack was about an inch or so long, and about 1/16" wide. Very hard to find with the heat shield hiding it.

    If none of this works (checking exhaust and using some injector cleaner in the gas), you might check the intake side to make sure you have no leak there. This will cause a very lean situation with inconsistant fuel-air mixture that may result in back-firing on deceleration.

    TQ
     
  4. alant123

    alant123 New Member

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    Hi Thabnks, It runs and starts perfect. I will take a look for leaks. It only seems to do it when it is hot....... When it was on a long run yesterday bringing it back. The back cyclinder started misfiring and cut out............. It was fine again after a few minutes
     
  5. glider

    glider Veteran Member

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    Just a thought here with things that were mentioned. Back in that year, there was a problem with the internal wiring inside the insulation breaking near the injector plug. Do a wiggle test with the engine running at full temps on the wires near the injectors and see if the engine misses when you do it.