2002 road king classic w/ fuel injection. rinehart true duals, vance and hines fuel pak, k/n filter with no backing plate, just the chrome cover. 57K miles. Interminent problem, the bike will idle slightly funny so I go to crack the throttle a little bit to give it some rpm's, bike wants to die. I left off the throttle just as fast as I cracked it and it goes back to idle. Also when I'm going down the road and I shift, pull the clutch in, shift, let clutch out and give it throttle the engine studders a couple times real bad and then takes off normally. Then I decided to remove the fuel pak entirely and rode it easily so I wouldnt ruin the motor from being too lean. Did not do any symptoms that i just got done explaining for 40 miles of town and highway riding. Stopped for twenty min, took back off again. Engine did fine for a bit and then the problem came back. Seems to be the symptoms are worse with tuner on.
My buddies seem to think that it could be fuel pump is going out and the tuner is making more demand for fuel compared to no tuner. I thought it might be the coil packs but one friend thinks that coils last for a long time and fuel pump is pretty much the culprit. I work on cars and CAT tractors mostly so im not overly familar with harley stuff just yet. Any insight to testing or diagnosing these problems would be greatly appreciated!

-kevin 2002 Road King Classic FI

 

Did you check the fuel filter. Maybe due.

 

Ive been told that the Fuel injected bikes do not have a filter but they have a screen or sock. Im not sure and im still researching and asking questions about the set up of the fuel system. Anymore insight you have to offer?

 

Fuel filter is in the gas tank.

 

Do you have your pipes, air cleaner and fuel pak mapped. If these are not in sinc then you will have the type of issues you explained.

 

yea, Ive been riding with the tuner since last july... Id esimate close to 3000 miles with no problems like this. Im wondering with so many miles if it isnt an air sensor. Like a MAF or MAP sensor going bad. The engine sometimes will increase idle speed up to 1500 rpm or so slowly (while at a stop light or such) and then slowly creep back down. while it is doing this and I crack the throttle it will either choke itself and want to fall on its face or it will increase rpm and hang up there for a minute and slowly fall back down to idle.

 

Item #9! I'd start there. Prolly due. Could have gotten dirty gas. http://partsfinder.onlinemicrofiche....-PUMP-ASSEMBLY

 

so i found a small tube on the throttle body that looked like a vacuum line. it had no cover and other similar bikes like mine had a rubber cap there. so i put a rubber cap on it and retuned the fuel tuner. went to vance and hines site and went thru my modification list and printed out the process and values that i needed. Ran good for like a mile. So I think that it happens mostly when the butterfly in throttlebody goes from closed(relaxed throttle cable) to any kind of throttle twist. once the butterfly is open and im cruising down the road it doesnt do anything bad. I shift, closing the butterfly as i pull in the clutch, then open the butterfly up with the throttle and it starts choking and chugging for a minute then rides fine until I let off the throttle again. It seems like the air sensor or MAP? sensor isnt able to read correctly at lower air flows? im not sure. Because I can run higher rpm and really give it some throttle and it runs great.... that makes me think its not a fuel pump problem. But I can be wrong, I am clearly not a professional and not a know it all haha

 

Could also be a vacuum leak.