So what's the problem!?!

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Cooter said:
So, whats the fuel pressure? Or were you hoping sea foam would 'fix' it. Hahaha.. Sorry...:black_eyed:

have resorted to a simple 90* pick for the lock ring with pretty good success. Remember, all you are doing is getting the tabs over the moulded barb on the line.
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I know, kills me to not be able to check it. I used the 2 pick trick to remove the stock connector but couldn't get it to release until the one tab broke, it was brittle from heat and to get a 4 tab release with the pick is next to impossible but the 2 tab one I replaced with should be no problem with the 2 picks.

I purged the fuel line at the fuel rail into a clear water bottle before I drained the tank. The gas was fine with no contamination, the sea foam was added for the tank and injector tip to help incase of possible sediment.

I should have said the pressure "could" be checked but not with what is provided in the kits. What is needed would be 4 hose clamps 5/16 fuel line the pressure gauge with "T" connection and a special brass connector at the pump end with barb to clamp the line to. This setup would allow for garage check but I wouldn't try to ride the bike with this setup. I could only find one picture of an XB with a fuel pressure gauge hooked up and it was Twin motorcycles, even then you couldn't see how it was hooked up. I would guess they spent the money and made up a dedicated setup with the proper stock ends needed to quickly hook up and test.

Once I had the line in I tried the bike normally, then hooked to ECMSpy and turned off 02/BAS/Closed loop idle to rule out what I could, that leaves TPS/CPS/AIT/Head temp only and I had no change. Even though it's erratic in a way it is a consistent erratic in that it doesn't care about temps or where it is RPM wise. If it was pump pressure it would be hard to go from 2k to 5k or 6k without some kind of hesitation I would think but this doesn't seem to be a problem. I wish those that have diagnosed the CPS running bad could throw in their 2'cents.
 
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cps always back-fires thru the intake snorkel when "coming back online" so to speak. and enough nose-cone heat will typically make it go crazy. and a cps on the way out also typically dumps a "plug to misfire" code either front or rear into fault code storage. hoping you don't have a failing ecm unit but before anything else you really need to do the following:
1-warm motor----run a simple compression test with WOT
2-remove the fuel pump and check for chafed or split wires.
your symptoms mirror those of some faulty pumps i've replaced in the past.
 
lunaticfringe said:
cps always back-fires thru the intake snorkel when "coming back online" so to speak. and enough nose-cone heat will typically make it go crazy. and a cps on the way out also typically dumps a "plug to misfire" code either front or rear into fault code storage. hoping you don't have a failing ecm unit but before anything else you really need to do the following:
1-warm motor----run a simple compression test with WOT
2-remove the fuel pump and check for chafed or split wires.
your symptoms mirror those of some faulty pumps i've replaced in the past.
Click to expand...

The back fire through the intake is absolutely terrible right now, yes.

1.) Could do a compression test and would like to know where they are at anyway for peace-of-mind but what is meant by "test with WOT"???
2.) Not apposed to pull the pump assembly and giving it a thorough inspection, don't want to possibly tear those large O-rings though... PITA to source in this small town.

As for CPS failures, it appears they can have varying degrees of showing symptoms from slight to heavy, getting worse with heat or not... etc, at least form the threads I can find on them. You are the only person stating a code associated with one gong bad that I have seen so far, I wish that were the case here, love it when the ECU can say "hey look over here". I hope someone comes through with one I can borrow or buy on the cheap! I'm seeing if an electrician who has a second house out here has an oscilloscope I can borrow the next time he comes out.

EDIT:

And... he doesn't have one but may be able to borrow one and won't be out for a couple weeks... someone PLEASE come through with a sensor and I'll ship it right back I promise!!!
 
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1.) Could do a compression test and would like to know where they are at anyway for peace-of-mind but what is meant by "test with WOT"???
2.) Not apposed to pull the pump assembly and giving it a thorough inspection, don't want to possibly tear those large O-rings though... PITA to source in this small town.

1-any leak-down or compression test must always be done on a warm motor and WOT is wide-open-throttle for either test.
2-the pump o-rings are typically reuseable. clean with denatured alcohol....NOT lacquer thinner....coat with O-ring sil based lube and reinstall.
 
Thanks lunatic,

Yeah when I read WOT I was thinking you were referring to WOT in a running condition... to clarify, anyone seeing this he is referring to the throttle body butterfly being in complete open position to get the proper compression/leak down reading. It could just be me but that is were my brain went when I read that. Also if someone sees this, compression should be 120psi or above.

I'll pull the pump of course, I was just kind of complaining indirectly I guess and that with my luck they will need replacing... I haven't seen them sourced in any of the pump threads I don't think? Someone said they had luck with the local hydraulic shop and another said McMaster-Carr if I remember right.
 
If the fuel pump o-rings come out ok (and they should), they may seem too big to put back in right away. Don't stress. let them dry out for a day and they will 'shrink' back to being tight on the assembly and will re-install easily with a little lube.

And Lunatic is right (of course:D) about not using lacquer thinner to clean them
 
Cooter said:
If the fuel pump o-rings come out ok (and they should), they may seem too big to put back in right away. Don't stress. let them dry out for a day and they will 'shrink' back to being tight on the assembly and will re-install easily with a little lube.

And Lunatic is right (of course:D) about not using lacquer thinner to clean them
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thanks for that shaughn. lowkey....look at the thread i just initiated. should be of interest to you.
 
Little update:

first thanks lunatic, I saw your post about the seals, the rebuild offerings from http://motoenthusiasts.bigcartel.com/product/fuel-pump-kits looks to be a good place to go depending on what I need. I borrowed a compression tester but of course there isn't an adapter for the 12mm size of the buell plug. I checked with autozone on the rental tester they offer as well but that one only has the 14mm plug too. So I ordered an adapter kit from amazon that will be here today. I only held off on pulling the pump to get the compression numbers before I see what's going on fuel wise. While I've been waiting I played with the CPS advancing it slightly and retarding it slightly, while it's not a black and white answer if it is working properly or not the adjustments are changing the timing, still could be going bad but as of now it is leading me to believe it is working as it should for now.
 
Alright boys pulled the pump yesterday and here it is















So it all looks like OEM condition with OEM parts except either someone put that shielding over the problem area of the wires or a dealership did and there is that one black zip tie holding the wire connection for low fuel light. I pulled back the shielding on the wires and they have zero rub on them, all connections were fully seated and tight. The accordion fuel hoses show zero wear... really this thing looks like I just ordered an pulled it from a box. The fuel tank was as clean as the day the bike was made. Only one weird thing is this paper thin green piece of plastic was in with the pump when I pulled it and I can't figure out what it is.

So what to do next?
 
Cooter said:
I'd check the fuel pressure....
Click to expand...

So the only way I can come up with doing that is to cut the line and use the pump side connection. I searched and searched for a connection like that but closest is a banjo fitting and the pump side has a slight taper to it so I don't think it will work. How are people determining that the pump or regulator or o-rings are bad without testing it as you've said? I still haven't found anyone except TWIN that has an XB hooked up to a pressure gauge. I haven't disassembled the pump setup yet but I'm wondering if everything from the other side of the housing can maybe be tested with regular fuel line and clamps?
 
It's in the service manual. You disconnect the fuel line, there is a quick connect located under the air box baseplate. There's also a part number for the gauge although you should be able to find a universal one at harbor freight.
 
Simplymichaeljr said:
It's in the service manual. You disconnect the fuel line, there is a quick connect located under the air box baseplate. There's also a part number for the gauge although you should be able to find a universal one at harbor freight.
Click to expand...

Have you been following my thread at all? I've already gone through replacing that end of the fuel line... of course at $$$$ anything is available/possible I have and rented a kit that had about every possible connection in it and no you can't check the pressure unless you pirate the connections from the existing line, then you have to rebuild it or buy new which I'm not trying to do.
 
Alright update time:

I found the time and gathered up everything to test the pump pressure and flow. I ended up having to cut the repaired fuel line again at the pump end to use the connection to test. At this point the line is to short to repair so I ordered a new one from Surdyke at $38.00 shipped (P0464.02A8A - FUEL LINE, PUMP TO RAIL). I put the pump in a bucket next to the bike and used the pump wiring and the kill switch for testing purposes. I have the coil/wires removed so no chance of spark.

Results:

kill switch on pump priming 51psi
steady hold of 49psi
2.4oz of fuel after 2 pump primes at 5 seconds = 13.5GPH

Trying to find the specs on the OEM pump lead me to the Walbro 521 which is rated 12 Volts with 45 PSI Pressure. Pumping out 16 GPH @ Outlet. So I'm down 2.5GPH but this is through the OEM filter and somewhat crude measurement on 10 year old system.
 
Pulled the injectors yesterday and they tested out fine, spray pattern nice and clean, so that makes the whole fuel system in good health. Waiting on the pump to rail line to come in then it's back to it. While I'm waiting I pulled every connection except for 2 or 3 down by the CPS connection, so far all are in tip top shape. Open to look at anything else anyone may have an idea while I wait, once the line is here and in I can go back to running bike tests.
 

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