2006 FXST Check Engine Light

[vindacator]

2006 FXST, 88" stock except for a/c and V&H 2 into 1, Engine starts check Engine light comes on for a few moments goes back off. While riding it comes back on in  the upper rpms i'd says 3800 or above and stays on. when Engine speed goes down the light will go back off. It has no misfires or hesitations. Each time you accellerate it will come on slow down it goes off.

[Ironpig9]

  My 02 RK started throwing a code a while back. The light would come on, go off as the system cleared the code, then a while later come back on. I could never pull the code. Took it to my wrench and he pulled the code - intermittent front cyl. firing (or incomplete firing). Audibly you could never hear it not firing completely. He cleard the code and it's never come back on. He said it's kind of a ghost code in that a cheap plug, or loose plug wire can cause the code. The bike always ran fine with or without the check engine light on.
You might run it by a shop and see if they can i.d. the code and clear it. Good luck.

[vindacator]

Is there a way to flash out the trouble codes?

[vindacator]

Problem found tourned out to be rear cyl plug wire not push on all the way. Didn't misfire but was enough connection error for the ion sensing to detect a wek fireing cylinder