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Dragging / Surging 2003 FLSTFI

Almost sounds like it is taking a little longer for the fuel to get to the bike, I would look at the fuel system, maybe run some cleaner through the bike, I think maybe Seafoam makes a cleaner if I am not mistaken.
 
Almost sounds like fuel pump pressure. That would sure make it hard to start and also would give surging due to leanness.
If fuel pump pressure is as critical on HD's as it is in the automotive industry, I would check it. Seven year old pump sure could be low on PSI. It would only have to be a little low for you to have drive-ability issues.

It's either that or an injector with restricted flow or bad spray pattern.
Take a look and see if there is an easy way to measure fuel pump pressure.
 
I put some Marvel Mystery Oil in the last couple of tanks. Do you know if I can get Seafoam at Autozone?
 
Do not know, I know Advance Auto parts has it. If you ran a good cleaner and still no luck, especially a few times, I would think you need to look into your fuel filter, a friend just changed his on his 09 with 6000 miles.
 
I just looked in my service manual and it says to refer to the Softails Electrical Diagnostical Manual for trouble shooting the EFI. Unfortunately I don't have one.
It is possible that the fuel filter is clogged because I haven't ever replaced it.
 
I don't know about your 2003 but on my '09 FXDL there is a fuel filter attached to the fuel pump inside the tank and the service manual does give a specification for fuel pump pressure at 55-62 PSI. It is not clear if this is the raw pump pressure before regulation. To me, that is a very high pressure to go directly to the injectors. I also don't know yet how the offset of intake manifold vacuum is handled.

But none the less, I would think your filter would need to be changed by now. I found this info in the basic service manual.
Note that there is also a fuel "sock" as well as the filter. I don't see a pressure regulator in the tank. It may be built into the Fuel rail next to the injectors themselves but not sure.
 
Thanks everyone for your replies.
Well I went and got some Sea Foam and then rode for about 78 miles (God I love Texas, 63 degrees @ 9:45pm). This is what I noticed: First off almost immediately I noticed better throttle response. I only put about 2 gal. of gas in the tank because I didn't want to have to worry about draining 5 gal. of fuel.
Well as i said it was running smoother but I could still feel the dragging / surging and as time went by it did seem to worsen. Glider your link about the pin holes may be on to something.
After about 55 mi. I decided to run through the gears at full throttle and after I hit 80 mph I backed off. Then almost immediately it started to cut out. It did this several times. I also had to give it more throttle to maintain speed like it was starving for fuel.
So at this point I'm thinking that it is either the pin holes in the fuel line causing it to not maintain fuel pressure or the fuel pump is not pumping at the correct pressure. And maybe the fuel filter is clogged.
I don't have any way of checking the pressure so I may have to take it to the dealer to have it checked out. I'll have to re-read Gliders link first to see if I can get by without taking it to them.
Once again thanks for all of your replies,
Randall
 
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