I bought a 1998 ultra classic about a month and a half ago. It is fuel injected and has about 25,000 miles on it. Since I bought it it has run really good and I put about 2,000 miles on it so far. Today though it just isnt running right. When I get on the gas it really hesitates and seems like the engine is missing. Also I noticed that at idle my rpms went from about 800 rpm to about 1300 rpm. When I give it gas either stationary or to speed up, the engine just falls on its face. So far I pulled the spark plugs and they looked good and I also put some heet in the gas tank to eliminate the possibility of moisture in the gas. Any Ideas what the problem could be? Possible dirty fuel filter?

 

It could be a pin hole in the fuel line that runs from the fuel pump inside the tank. Had this on mine a few years ago and made it run quite erratically. Could also be dirty injectors. There are a couple of other things it could be as well. They escape me at the moment.

 

I rode it a little more since my first post and added some fuel injector cleaner. I rode it for about 40 minutes or so trying to get a better feel for what is doing. The problem is intermitten. It will run good for a while then it will start cutten out. When its not running right I have seen the idle rpm as high as 1700 rpms. When it idles that high I cant hardly pull out it seems when I give it throttle its not getting any fuel. When its running right the idle rpm is between 900 and 1000 rpm. Could it be that my fuel pump is going bad? I will check the fuel line for cracks or small holes tomorrow. I don't know if its related or not but ever since I got the bike my fuel gauge has acted kind of crazy. Every now and then it will go all the way up to full (this happens while I am driving not pulling out or on the brakes when the gas would be shifting) and my gas light comes on even though I am at like half a tank or so. After a minute or so the gauge goes back to normal.

 

Have you noticed if it is when the gas tank is lower? Fill the tank all the way and see if it does it. If not then most likely it's fuel line. I don't know with the high idle though.

 

I only had about 50 miles on the tank when this started

 

With 25000 miles on the bike,I would replace the fuel filter and inspect the fuel lines in the tank and go from there.
The filter kit should include one hose.It's the hose that comes up from the bottom of the tank that needs to be inspected for holes.This hose does not come with the kit.

 

I checked the fuel lines today they looked good. The one thing that seemed odd to me and I dont know if it is the way it should be is where the fuel lines (I have two of them) come out of the gas tank. The have a metal elbow that bolts onto the tank and they seem loose. Not loose at the tank but the elbow below the nut I can easily swivel back and forth. Don't know if my description makes any sense or not.

 

Check the fuel lines inside the tank.

 

Normal. They swivel freely.

 

That's a quick connect to the tank. It will swivel.

If your gas gauge is doing weird things at the same time it's running bad, I'd check your electric grounds and battery cables. Make sure you don't have a corroded wire that is giving erratic signals.

As others have mentioned, check the fuel lines inside the tank.

Good luck.