Fuel Pressure Fault code

[Ggeezer]

Hi again, not been here for a while mostly because my bike has been running well and I spend most of my time riding it. Recently, I turned on my key and the CEL came on for 3 seconds and went out as it should and then it came back on and stayed on. It didn't matter if the bike was running or not the same thing happened every time I turned the key on. I pulled out my trusty Buelltooth and phone and checked the error codes, there was only one "0 Fuel Pressure Fault". That's what is wrong as far as the ECM is concerned but the bike runs perfectly otherwise, it starts cleanly every time, runs at all engine speeds as it should and handles full throttle bursts as it should.

What I have done to the bike over the years, replaced the fuel pump, replaced the fuel rail pressure sensor. I checked the fuel pressure when the bike is running with ECM Droid and it hovers between 40 and 50 psi. A little research revealed that the fuel pressure should be tightly controlled at 49 to 50 psi and if that is true would probably be the reason I have a CEL.

I am wondering what you guys have to say about this. Have any of you had any similar experiences? Have you got any ideas on how to fix this issue and permanently clear the code.

Running my bike under these conditions does not seem to have had any negative effect so I guess I can just put a piece of black tape over the CEL if I can't sort this out since having the CEL light on all the time isn't really telling me much anyway

Anyway, here are the bike specs:

2010 Buell XB12Scg

[Cooter]

I didn't know the 2010's got a fuel pressure sender. Thats cool. It can't be for tuning so it must just be there to turn on the CEL if theres an issue... like yours is doing. Same with the 1125's, they were all DDFI-3 as well.

Anyway, yes, it should be at 49psi and rock solid, even at WOT. I would recommend a COMPLETE fuel pump re-build kit that includes the pressure regulator and hoses (they get pinholes). Contact Barrett on here or Rev-Mo.com for high quality kits and stay AWAY from the e-bay stuff, it's terrible.

[Ggeezer]

I didn't know the 2010's got a fuel pressure sender. Thats cool. It can't be for tuning so it must just be there to turn on the CEL if theres an issue... like yours is doing. Same with the 1125's, they were all DDFI-3 as well.

Anyway, yes, it should be at 49psi and rock solid, even at WOT. I would recommend a COMPLETE fuel pump re-build kit that includes the pressure regulator and hoses (they get pinholes). Contact Barrett on here or Rev-Mo.com for high quality kits and stay AWAY from the e-bay stuff, it's terrible.

That's the thing, I rebuilt the pump a while back and all was good until this code was thrown. I also went to the trouble of installing the original pump and the results were the same. I have since put the new pump back in (getting really good at that by the way, in and out in under 45 min.) I guess its possible that I have 2 faulty pumps and pressure relief valves but... The thing is, the fueling system on these bikes is pretty simple and I can't really see where it could be going off the rails here. There are no leaks visible on the outside and unless the pump housing is cracked or maybe a dirty injector is spitting fuel into the intake all the time I don't know what else it could be.

As for the fuel pressure sender switch on the fuel rail, I believe that was a 2010 only thing and it is there to tell the ECM when to cycle power to the fuel pump so that it is not running all the time. Prior to 2010 I believe the pumps just ran all the time and relied on the pressure relief valve to bleed off pressure if required.

[Cooter]

There is a U-shaped outlet hose from the pump that is internal in the tank. That hose likes to get pinholes and leak internally in the tank, it gets worse and worse until its not enough to feed the regulator and the pressure drops from the rock solid 49 psi its supposed to have until:

"the fuel pressure when the bike is running with ECM Droid and it hovers between 40 and 50 psi" which is PROOF there is something DEFINITELY wrong with the fuel supply. I know you don't want to do it again, but that failed test is PROOF there is something DEFINITELY wrong with the fuel supply.

IMO it's sure worth 45 mins to find out. Those hoses are very special and should come in a complete re-build kit. Take it out, stick the pump assembly in a bucket and jump it to a battery, plug the end, you'll know right away.

Hope that works for ya

edit: Whats you AFV? I'm betting it's nowhere near the neutral 100 it's supposed to be because it's been compensating for low fuel pressure.

[Barrett]

Gord: Got your PM and email address and thanks. I'll respond this morning. On your pump situation:
The 2010 XB pump is unique to that year. Easily identified by the large metal "W" shaped clip holding the regulator to the housing...large black plastic motor shield...wiring harness unplugs from the pump body itself. The pump is unique to 2010 XB models and as you mentioned, fuel delivery system also unique to 2010. Pump is cycled on and off by the ECM receiving pressure readings from the fuel rail sensor. All prior XB pumps charge the system with key and kill switch on...then shut down till engine starts...then run continuously. Your pressure sensor is simply telling the ECM that the rail pressure is substantially below minimum, signaling the CEL...the stored fault code...the pump to run near continuously. You have either a faulty pump regulator or pump motor, or both.

You stated pump "replaced". With what???? If it was rebuilt by a novice with online Quantum parts, therein lies your problem.

[34nineteen]

There is a U-shaped outlet hose from the pump that is internal in the tank. .

You're a U-shaped outlet hose.

[Cooter]

You're a U-shaped outlet hose.

"Thats what"

-She

[34nineteen]

stay AWAY from the e-bay stuff, it's terrible.

What about this? Seems like a quality product and the seller is a stand up, American patriot (not to mention smart and handsome) from Leola, PA.

https://www.ebay.com/itm/17571813001...Bk9SR96w2-aAYg


Not some hippie living in his El Camino in El Segundo.

[kz6fittycent]

What about this? Seems like a quality product and the seller is a stand up, American patriot (not to mention smart and handsome) from Leola, PA.

https://www.ebay.com/itm/17571813001...Bk9SR96w2-aAYg


Not some hippie living in his El Camino in El Segundo.

Glad you posted this! Now I know where I can get the o-ring kit for my fuel pump.

[Cooter]

What about this? Seems like a quality product and the seller is a stand up, American patriot (not to mention smart and handsome) from Leola, PA.

https://www.ebay.com/itm/17571813001...Bk9SR96w2-aAYg


Not some hippie living in his El Camino in El Segundo.

That stuff is ok. They use Viton that has been mined from the peaks of the Allegheny mountains, carefully transported through only the best covered bridges by hand-built Amish wagon train and then refined in the cauldrons of only the finest of churners.