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Discussion Starter #1
Hey guys!

I've already done the Loom Fix, just FYI.

I'm absolutely perplexed right now. I was having problems with my 2000 Blackbird cutting out, which ended up being the kill switch. After I fixed it, it ran perfectly... For one day. The next day I tried to start it, it just kept spinning. It started to grab for just a second, but would only idle *very roughly* for about 10 seconds, and then cut out. FI light is glowing steady. I know I'm getting spark, so I took the fuel rail off with the injectors. I tried cranking the bike, and it started squirting fuel. It wasn't a mist, which led me to believe that they might've clogged. However, the second I tried giving it any throttle at all, the injectors stopped spraying. I gave up then and there for about two weeks.

Just yesterday, I decided to have another look. The fuel rail was already off, so I decided to see if it was still squirting fuel. It wasn't. I put the rail back on the bike, and pull out my test light. All 4 injectors are getting constant power, but none of them are getting ground pulse. Does anyone know what might be causing this? I'm *reeaally* hoping it's not a fried ECU. Are there any sensors that may be giving it a 'no-start' condition?
 

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Grigby
Yes it's been done
Agree with fizzy drop the side stand and turn on the key and count the light blinks.
 

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Discussion Starter #5
Currently all that's showing is the sensor in the airbox. I've got the entire airbox taken off to get to some pieces. When the sensor is plugged in, the FI light stays on and shows no blinks.

Also, I was 100% wrong about the no pulse thing. When I try to start the bike, I can twist the throttle wide open, look down the throttle bodies and see fuel spraying. It seems to be missing some pulses, and its barely spraying any gas. The bike was working one day, and then it stopped the next. I am so confused... Maybe the fuel pump has gone bad? I hear it prime when I flip the kill switch. Maybe the injectors? I just replaced the fuel filter.
 

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The bike goes into a clear flood condition in the scenario you just did. It reduces or stops the injectors pulsing to help fire the bike when its flooded.

If the light is staying on when all the sensors are installed you still have an ECM issue. Page 5-12 list a series of faults that will keep the light lit. There is a copy of the service manual in the resources section download it and follow the T/S guide and let us know what you find. We'll try and help from there.
 

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Beestoys, if memory serves, deploying the side stand to get codes only works if the engine runs. Mujihana, bridge the 2 wire connecter in the tail (above the rear light) to reveal the codes + what beestoys said above.
 

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Yep forgot about that part of it fizzy.
 

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Discussion Starter #10 (Edited)
Well, I've got news. I plugged the AT sensor back into the bike and the FI light is gone. It's currently not throwing any codes. I checked my relays and they seem to be fine. My fuel pump is getting anywhere between 9.6 to 11.2 volts. Is that low, or is that normal? I didn't see what it's supposed to be at in the manual. Also, could the idle adjuster be at fault here? Maybe it got turned down all the way or something? I recently replaced my fuel filter with an aftermarket one with some extra tubing. I now realize that I might have put it on the wrong way. Would that slow the fuel flow down this much?

And exxelent, the hose is connected to all 4 cylinders, the fuel pressure regulator, and then to the MAP sensor. That's how it's supposed to be, correct?

Beestoys, what's with the clear flooding condition? I've never heard of it before. Is it something that can be tested? Can I turn it off manually? Is there a specific sensor that would be causing it to activate?

Thank you all for your replies, I don't know what I would do without this forum. I'm just an 18 year old kid learning how to put all this stuff together.
 

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That voltage is too low. Is the battery voltage the same? A load test of the battery should be done as a weak battery will cause many problems.
 

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Muji
No it's a feature of injected engines. When you open the throttle wide open the system senses that the engine isn't running and cuts or reduces the injector pulses.

Second excels advice. Connect your meter to the battery terminals and crank the engine over. If that voltage drops below 10 volts the bike may not fire. Each bike is a little different but the closer to 12 you are the better. 9 volts is a deffinate no run condition.
 

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sounds to me like low fuel pressure - the clue could be "you replaced the fuel filter", do you still have the old one ?

also since you are working around the fuel rail - there must be no leaks in all those little vacuum pipes - the FPR relies on that vacuum to work, if there is no vacuum (because of a leak) the engine will not start or run and show exactly the symptoms you describe
 

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Discussion Starter #14
Okay,

Battery load test: Battery is at 12.3 when not under load, and bounces between 10.2v and 10.6v while cranking, and dipped to 9.8 at one point.

Vacuum lines: I was wrong when I said "the hose is connected to all 4 cylinders, the fuel pressure regulator, and then to the MAP sensor". All cylinders are connected and run to the MAP sensor. Only cylinders 2 and 3 are connected to the FPR. Vacuum lines look functional.

Fuel filter: I do still have my fuel filter. I am working two jobs right now, so I don't have time to swap it out today. However, tomorrow I should be able to. And a question on this: If my dumb ass hypothetically submerged said fuel filter in water, would I be able to dry it out and use it again?

Fuel pressure: I would 100% agree that this seems like fuel pressure. I rented a fuel pressure test kit and couldn't find where to hook it up, got frustrated, and returned it. Beestoys helped me find the service manual, and in there I found where I should hook it up. Apparently it's directly on the fuel pump on the bottom of the tank. Who woulda thought. I'll see if I can rent it again on Friday, and I'll for sure try it out.

So my question is: Would any of these problems occur over night? That's what I'm stuck on here, and it's really confusing. Like I said, my bike started and rode perfectly one day, and then the next morning, it was bricked.

Seriously, you guys are a huge help. I'm too broke (and stubborn) to take this thing down to a shop, and you guys are giving me confidence in my ability to fix this thing. This forum is a beautiful. Thank you.
 

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Take your bike to a shop to troubleshoot? And you think you are broke now? And they wont fix it anyway.

Before you remove the fuel filter, do a flow test. As exellent says above, battery and/or pump voltage is low. Fix that first.
 

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Vacuum lines: I was wrong when I said "
the hose is connected to all 4 cylinders, the fuel pressure regulator, and then to the MAP sensor". All cylinders are connected and run to the MAP sensor. Only cylinders 2 and 3 are connected to the FPR. Vacuum lines look functional.


nothing will work if any of the vacuum lines are open - you will have no fuel pressure because the FPR will not function

let me put this a different way

on a running engine if you disconnect any of those vacuum pipes the engine will stop - just assume that to be true - IMO you are looking for a problem you have created yourself and if I was there with you I would take the time to explain it all

it was never your battery, you had an engine turning over - you replaced the fuel filter for no reason - you have all sorts of stuff disconnected and have likely caused most of the problems you are seeing now - you said the stop switch was faulty and yet you still have a bike that won't start

Don't know what else you may have disturbed

Time to get it all back together (especially those little vacuum hoses, all of them) - step back and start again...…….and I mean that with the greatest respect, I wish I could be right there to help you
 

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Take your bike to a shop to troubleshoot? And you think you are broke now? And they wont fix it anyway.

Before you remove the fuel filter, do a flow test. As exellent says above, battery and/or pump voltage is low. Fix that first.
the pump is running - most of the fuel pumped returns to the tank, unless there is something seriously wrong with the pump - that is not the problem, the pump will run fine on 9v never mind 11v, fuel pressure on the rail is controlled by the FPR which is controlled by the air intake vacuum - no vacuum = no fuel pressure
 

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Muji
If it's a paper element filter and you submerged it in water no it's toast. The fibers will swell and actually block flow. Gas although it's a liquid wont effect the filter media that way. So swap the old one back in. Stubborn is a good thing. Just be patient and temper yourself and with help we'll help you get it sorted
 

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Muji
If it's a paper element filter and you submerged it in water no it's toast. The fibers will swell and actually block flow. Gas although it's a liquid wont effect the filter media that way. So swap the old one back in. Stubborn is a good thing. Just be patient and temper yourself and with help we'll help you get it sorted
I have been through this very thing caused by a rusty tank, water will clear the junk from a blocked fuel filter but ultimately it needs to be replaced along with the source of the contamination, clearing the filter with water and then blown out with an airline will provide diagnostic information and get the motor running if that is the problem - been there done that
 
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