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Engine hesitation when accelerating

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Old Sep 20, 2018 | 06:57 AM
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Default Engine hesitation when accelerating

I have a 2003 FLSTC that is backfiring and hesitating when I accelerate. The more throttle I give it, the more it jerks. Eventually, it "kicks in" and goes. It cruises smoothly at speed or if I accelerate slowly. I have tried fuel injector cleaner, but it didn't help.
 
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Old Sep 20, 2018 | 06:59 AM
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Fuel filter dirty maybe, sometimes 1 injector treatment isn’t enoug, remember, it didn’t get clogged overnight...
 
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Old Sep 20, 2018 | 07:11 AM
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Thank you for your quick response. Is the fuel filter hard to change?
 
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Old Sep 20, 2018 | 07:34 AM
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There is no mention of a fuel filter in my service manual.
 
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Old Sep 20, 2018 | 09:23 AM
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It's at the petcock... see attached link #27

http://partsfinder.onlinemicrofiche....=44&c=0&d=2003 FLSTC SOFTAILŽ HERITAGE CLASSIC (CARB) (BJ) FUEL TANK SENDING UNIT ASSEMBLY
 
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Old Sep 20, 2018 | 03:21 PM
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Sounds a bit like the fuel pressure regulator housing in the tank has pushed off and you're losing fuel pressure. What you described sounds very much like what my bike did when the housing pushed off. They are notorious for that..

If you don't want to pull the fuel pump assembly out of the tank yourself, just ride it up to a dealer and have them check the fuel pressure. Just takes a minute.

I had a thread going on that problem a while back. Search it out and have a look.
 

Last edited by Pitbull_Dallas; Sep 20, 2018 at 03:28 PM.
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Old Sep 20, 2018 | 03:33 PM
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You say fuel injector cleaner. I sort of think you have fuel injection? But letters would be FLSTCI. If you do, the filter is in the tank from the top. If it is carb. Check screen at petcock. But first, remove the air filter and make sure you see a shot of gas looking back thru carb when you twist throttle wide open. A stumble is usually associated with accelerator pump for that extra fuel needed for that sudden increase with air from a rapidly opening throttle.

A stopped up filter on a carb bike will limit top speed or even the power to go up a hill. On a fuel injected bike, it will kill idle first long before it gets so bad to affect top end.

A cleaner is a waste in my opinion. If you dump it in a FI bike tank, if it does anything, all it does is screw up the tank, cause rust and then that dumps into the actual fuel filter and worst into the small screens in the top of the injectors.
On a carb bike, it rarely can open jets and just spraying in the opening of intake kills sensors by washing dissolved black crud up past o-rings and drying crud up in them.
 

Last edited by Jackie Paper; Sep 20, 2018 at 03:48 PM.
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Old Sep 20, 2018 | 08:27 PM
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Had same exact issue in the past took me a year to figure out. Turned out spark plugs wires were faulty 20$ fix.
 
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Old Sep 23, 2018 | 08:06 AM
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Sorry for the delay in responding to you. I made an appointment to have the pressure checked. One more thing though, it seems the problem is intermittent. I took the bike out a couple days ago and it ran like a top. I could not get it to hesitate at all. Great power and acceleration. Then yesterday the problem returned..
 
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Old Sep 23, 2018 | 08:09 AM
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My bike is fuel injected so I guess its code is flstci. Thank you for the tip regarding fuel injector cleaner.
 
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