Misfires or dies
Thread Starter
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6th Gear
Joined: Jan 2013
Posts: 10
Likes: 0
From: Florida
Misfires or dies
Stumped
01 Roadking is driving me crazy, started misfireing or just plain dying at about 1/4 throttle, doesn't matter what gear im in, but if I open it up it smoothes out.
The cooler the weather the worse it is. Runs better at high speeds sometimes,then switches up on me sometimes and runs better at low speeds.
No codes to read, switched plugs no differance, put ethanol treatment and injector cleaner, nothing.
Even the Harley shop has no clue.
01 Roadking is driving me crazy, started misfireing or just plain dying at about 1/4 throttle, doesn't matter what gear im in, but if I open it up it smoothes out.
The cooler the weather the worse it is. Runs better at high speeds sometimes,then switches up on me sometimes and runs better at low speeds.
No codes to read, switched plugs no differance, put ethanol treatment and injector cleaner, nothing.
Even the Harley shop has no clue.
Extreme HDF Member
Joined: Sep 2010
Posts: 14,744
Likes: 402
From: Phoenix '53, '88, '09 Big Twins
what have they done ?
is this an EFI or carbed bike?
stock or modified ?
efi, check fuel pressure and volume
carbed, then check carb...fuel flow first - petcock screen, float bowl for gunk.
set float level, clean jets, inspect diaphragm for pinholes
intake manifold seal
etc. etc.
start with the basics.
the more detailed you can be with your complaint- the better responses you will get.
tell us more, Mike
is this an EFI or carbed bike?
stock or modified ?
efi, check fuel pressure and volume
carbed, then check carb...fuel flow first - petcock screen, float bowl for gunk.
set float level, clean jets, inspect diaphragm for pinholes
intake manifold seal
etc. etc.
start with the basics.
the more detailed you can be with your complaint- the better responses you will get.
tell us more, Mike
Thread Starter
|
6th Gear
Joined: Jan 2013
Posts: 10
Likes: 0
From: Florida
Hey guys thanks for responses, its EFI, and its close to stock, I have a high flow filter and exhaust with a stage 1 map.
Is there a way I can check fuel pressure at home ?
The fuel pump has locked up twice, my engine light would be on and I could tell the pump didn't run the normal amount of time when I hit the run switch. I'd have to shut it off and on again several times then it would finally start.
My engine light does come on when I'm traveling at highway speed and it starts to act up, then goes out when it smooths out.
Nice ride Old Guy, you got a few years on me but I plan to still be riding untill they plant me.
Is there a way I can check fuel pressure at home ?
The fuel pump has locked up twice, my engine light would be on and I could tell the pump didn't run the normal amount of time when I hit the run switch. I'd have to shut it off and on again several times then it would finally start.
My engine light does come on when I'm traveling at highway speed and it starts to act up, then goes out when it smooths out.
Nice ride Old Guy, you got a few years on me but I plan to still be riding untill they plant me.
Last edited by Biker Boy 53; Nov 25, 2013 at 12:33 PM.
Extreme HDF Member
Joined: Sep 2010
Posts: 14,744
Likes: 402
From: Phoenix '53, '88, '09 Big Twins
harbor freight does sell a $24 fuel line pressure gauge- it comes with a bunch of fittings but I am not sure what you'd need ( I stayed away, far away from the early versions of H-D EFI)
given that you have had fuel pump problems in the past- pull it and chck the filter- could be clogged or failed...clogging teh fuel pump.
check teh internal hoses too.
the fuel pump is cooled by fuel so make a habit if running fuel levels high, rather than low.
check the wiring to the fuel pump too.
Mike
given that you have had fuel pump problems in the past- pull it and chck the filter- could be clogged or failed...clogging teh fuel pump.
check teh internal hoses too.
the fuel pump is cooled by fuel so make a habit if running fuel levels high, rather than low.
check the wiring to the fuel pump too.
Mike
just a thought...check the ECM connector...Mine was acting like that, almost like there was a problem with the TPS> and the connector was almost off. had to take a rubber mallet to tap it back down where the wire bail would engage to hold it down...just look at where the bail snaps on the connector. if the bail is not completely on, then take the connector off, put some dielectric grease on the connector and replace......make sure the bail is locked down....
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Thread Starter
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6th Gear
Joined: Jan 2013
Posts: 10
Likes: 0
From: Florida
Yes it has that early EFI system, but have had no problems over the last 12 yrs untill now, I assume the fuel filter is in the tank ( no its never been replaced) and from the pics in my service manuel I'll need to be a heart surgeon to get to it.
At the risk of sounding like a dummy where would I find the ECM
And thanks guys it good to have knowledgable folks to lend a hand!
At the risk of sounding like a dummy where would I find the ECM
And thanks guys it good to have knowledgable folks to lend a hand!
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Take the air cleaner off and look into the throttle body, towards the top on the sides you will see 2 small ports in there. These ports allow air to get in the bike with the butterflys closed, (at idle and lower speeds). If these ports are plugged up the bike will not run right. It's not uncommon for them to get gunked up over time. Try squirting some carb cleaner or sea foam in them and see if that helps you out. The bikes are also know to get pinholes in the fuel line inside the tank. With the bike low on fuel, open the fuel door and remove the gas cap, turn the ignition and run switch both to the on position and with your ear near the fuel cap see if you can hear fuel spraying inside the tank. If you do then you are a pinhole and as a result your fuel pressure is low. Other than that check for intake seals leaking. You can do this with spraying some carb cleaner around the intake with the bike running at idle. If the engine changes or the exhaust starts smelling like burning carb cleaner then you have leaky intake seals. Just be careful you don't spray the cleaner into the air filter or you'll get false positive results.
Cruiser
Joined: Nov 2007
Posts: 134
Likes: 1
From: Millbury, ma
I just went through an almost identical experience with my 03 RKC. Dealer had no clue. Replaced the fuel filter, no change. Even tried replacing the Power Commander with no results. Turned out to be a bad plug wire. Had a worn spot half way through. Take a look, it's worth a try.