I own a 2004 dyna wide glide and the other day I noticed this noise once my "check engine" light kept coming on. Fortunately I could hear it over the exhaust (screamin' eagle slip-ons) its constant while it idles but of course I can't hear it once I get up to speed. I did the diagnostic test, and I got the b1004 fault code. could this whirring/whining noise be related to the fuel system? I believe that is what that code is for. any help would be appreciated.

 

If it's injected it may be the fuel pump. Does it vary with the fuel level?

 

Is the '04 fuel injected? If so, that's probably your fuel pump making the noise.

B1004 is fuel sending unit low. Basically states (in the '08 manual) "if the voltage on terminal '9' of the connector (into the fuel tank) exceeds the lower limit for greater than or equal to 15 seconds, DTC B1004 will be set."

Could either be the fuel level sending unit, the fuel guage or the speedometer.. all three can affect the throwing of a B1004.

I suppose it's possible that if your fuel pump is starting to go out, it could be dragging some voltages low around the speedometer and fuel sending unit.

Just a thought.... in case there is a similarity between the '04 and '08.