XB9S died during drive at a stop sign, now it won´t start again

[MJsweden]

PROBLEM SOLVED-BAD FUEL PUMP


Hello everyone.
I bought an Buell XB9s 2003 about half a year ago. It had a bad fuel pump and ran poorly with irregular fuel delivery.

I knew that fact when i bought it, but had already an Buell shop intended for doing a complete overhaul of the bike. Including a new fuel pump.

They changed fuel pump, spark plugs, cleaned the injectors with intended machines for it. And then a complete service of the bike.

After that the bike has been running great without any problems for about 1000 miles. On my way to work i filled up the tank with premium gasoline (as always). Then i rode on the highway for 40 miles, got of the highway onto a road with 30mph and rode that about 3 miles. Then came to a stoplight and the bike dies. Then it would crank but did not start. Luckily i was already close to my work, and had a ecm cable. So i hooked it up to the ecmspy, but it didn´t show any trouble codes from what i could find.

I took it to a friend who has a carshop (the buell shop is far away from me, roughly 250 miles). He is a well respected general mechanic and sometimes work on bikes. I tought he could do a first form of troubleshooting.
The bike starts with fuel in the throttlebody.
The fuelpressure seems good, but it feels as if something is "telling the bike" to not push the fuel into the injectors? Can the cam sensor cause this fault? Or is there another sensor that can cause problems? What could it be?

Thankful for your input, i have found similar topics. But i felt that i might as well put up a new one to keep more up to date for myself, hope it is ok.

 

[Cooter]

Thanks for the detailed post!

If it cranks, all the safeties are OK.
If it starts by spraying the TB. It's a fueling issue.
So, what do you mean by this?

The fuelpressure seems good,

It 'seems' to have 49 psi on a gauge when cranking and under load? Because thats how you test a fuel pump.
https://www.rev-mo.com/product-page/xb-fuel-pressure-tester
Then you will know where to look next, like if you don't have 49 psi... commonly compromised fuel lines (pinholes) internal in the frame/tank, clogged fuel sock, bad pump, etc.

If you did test and do have 49 psi,
You can put a test light on the each injector plug and see if they're getting signal while cranking.

If you're getting signal to the injectors and still no fuel, pull them out. Any half decent repair shop can test injectors from a rig designed for it or with Brakleen and a 9v battery.

If it's not starting with the injectors flowing fluid when activated and you're getting 49psi of fuel out of the rail then by golly call a Priest.

 

[ztied]

I had similar experience. Bought axb12r that appeared to have sat since 2016. After rebuilding fuel pump, and getting it running, the cam sensor was causing the issues like you describe. After pulling the cover for cam, I could see melted goo around the sensor,
Liston to advice from guys above first, it is usually something simple. You may have to change plugs after getting it sorted out, from the continuous starting also.

 

[Cooter]

Glad you got yours fixed up ztied:up: Hope you're still riding a bunch And yep, a bad CPS would cause the injectors not to fire, but also wouldn't fire the coils... so it wouldn't run with fuel sprayed down the TB like his does.

He should figure his out, pretty straight forward diagnosis.

 

[Barrett]

So the pump is priming nicely, but there must be a leak within the fuelpump assembly or something wrong with the new one.
unfourtunately i bought the pump online and not from them. But they will fix it nevertheless.

Did it ever occur to you to commence this thread with "I bought a new bargain-priced non-authentic fuel pump online, had it installed, and now my Buell won't run."
My God!

1-This pump is NOT pressurizing/priming the fuel system. You are only hearing the electric motor activating. It is NOT an authentic New-In-Box OEM fuel pump that only myself and few others worldwide still have in stock. Probably some bargained priced Chinese garbage masquerading as a suitable substitute.
2-Your pump has either an inferior motor....sub-standard regulator.... faulty high pressure supply line...or all three.

You got what you paid for. Good luck.

 

[Cooter]

He's right ^^^
The non-Walbro pumps on e-Bay are significantly cheaper for a reason:down: It's common to come with the wrong regulator, that will cause all sorts of tuning and running issues, and a hesitation under load could absolutley be a result of that. They will also come with cheap hose that won't last long when submerged in gas and the pin holes will drastically reduce fuel flow and pressure as well.

It's awfully tempting to go cheap, but now you're in it the trouble and the labor X2... Don't worry it's a common new Bueller mistake. OE quality kits and replacements can still be found, PM Barrett is the easiest way

I would caution against having the shop 'tune it' before you know if you even need it. If the PO put on the filter and a legit Buell race exhaust, maybe he put the right tune in? IDSpd.com is the company that sells complete ECM's with the right tune for those simple mods. Plug-n-play. Free internet tunes can put you right back in the position you are in right now..