09 Ultra did the exact same thing when it was out of warrantee. I took it back to the dealer they fixed it for free. Plug and or pins go bad behind the air cleaner. It seems to be a common problem. Has not happen again.

 

Thanks Saxton, I'll see if the dealer can look at it for me. Mine is a 2008 Ultra. As bad as I hate going there my other shop probably know nothing about TbW.

 

I haven't changed the bars, but I did put chrome buttons on all the controls.

 

You throttle lever is a fancy switch that controls the small motor on the throttle body that opens the butterfly air passage. Controlled by the ECM and a bunch of safety checks. It actually made the throttle body cheaper by $200 and eliminated the IAC (idle air control) They also combined to other sensors into one. It's main function is to prevent shutting all the air off to the engine when coasting down. You can do this with a steel cable that did work butterfly. This greatly increases certain smog polluting emissions. It's hard to see it on a Harley, but you can on new cars with a precision tac. If you let up off the throttle and coast to a stop at a red light, you can see the tac bump up a few 100rpms as you coast down. The ECM is reading the too rich mixture and adding air to reduce it. Read the full description on Wikipedia.