01 1300 hayabusa flooding

[Brock371]

So I have a 2001 hayabusa that is struggling to start. It will start fine cold but after it runs for a bit and I shut it down it will just crank but not fire. The only way that I'm able to get the motor to run is to hold it wide open. It will then fire but acts as if it was flooded. It shoots out black smoke and once that clears up the bike seems normal. It will idle just fine and run great. The moment I shut it down it will do the same issue when I go to fire it up. Has brand new battery.

Thanks for your help!! Any insight is great.

 

[sixpack577]

Does it have a TRE, Power Commander, or anything else added?

 

[Brock371]

Does it have a TRE, Power Commander, or anything else added?

No, it's just stock. Played with it a little more tonight. If I give it a little throttle right upfront it starts but you can tell its rich with the smoke and cleans up after about a second. If I keep cranking and then add throttle I have to go WOT to get her to finally fire up. Rail pressure is 43psi. When running the bike seems completely normal. Runs strong but will smoke a little when the throttle is cracked open hard.

 

[Kiwi Rider]

If the coolant temp sensor is faulty it can cause this sort of symptom. I've seen this on EFi cars that I've worked on.
If the CT sensor is always reading a cold temp because of the faulty reading the ECU gets the message to add more fuel. This could be why it starts fine when cold, but floods when warmed up. Maybe.
The other one to check is the MAP sensor.
Did this problem suddenly occur or gradually got worse?

 

[Brock371]

If the coolant temp sensor is faulty it can cause this sort of symptom. I've seen this on EFi cars that I've worked on.
If the CT sensor is always reading a cold temp because of the faulty reading the ECU gets the message to add more fuel. This could be why it starts fine when cold, but floods when warmed up. Maybe.
The other one to check is the MAP sensor.
Did this problem suddenly occur or gradually got worse?

It suddenly occurred. Would my coolant gauge still read fine if that sensor wasn't working? The gauge seems to be working like it should.

 

[Kiwi Rider]

It suddenly occurred. Would my coolant gauge still read fine if that sensor wasn't working? The gauge seems to be working like it should.

The engine temp gauge on the dash is working off a separate sender unit which is located in the radiator.
The engine coolant temp sensor (ECT) is located in the back of the cylinder block and sends info directly to the ECU. It is also linked in to the AP sensor (Atmospheric Pressure, also know in the car game as the MAP sensor) and these have a direct effect on injection time.
It's a place to start looking at I guess.
Good luck, let us know how you get on.

 

[Brock371]

The engine temp gauge on the dash is working off a separate sender unit which is located in the radiator.
The engine coolant temp sensor (ECT) is located in the back of the cylinder block and sends info directly to the ECU. It is also linked in to the AP sensor (Atmospheric Pressure, also know in the car game as the MAP sensor) and these have a direct effect on injection time.
It's a place to start looking at I guess.
Good luck, let us know how you get on.

So last night I scratched my head a bunch and I believe I fixed my issue. I noticed that the Map sensor and the sensor on the block were identical green plugs. I thought maybe these had been accidentally switched so I swapped them and this has seemed to correct my issue. The bike now starts fine every time it seems. Weird I know. I recently bought the bike so I assume he had them backward.

The next thing I'm trying to get squared away is my fuel pressure. It has an external FPR that sits between the fuel rail and the fuel pump. The FPR has a nipple that I assume is supposed to be connected to a vacuum source. Would connecting this to the inake vacuum lines work?

 

[Kiwi Rider]

So last night I scratched my head a bunch and I believe I fixed my issue. I noticed that the Map sensor and the sensor on the block were identical green plugs. I thought maybe these had been accidentally switched so I swapped them and this has seemed to correct my issue. The bike now starts fine every time it seems. Weird I know. I recently bought the bike so I assume he had them backward.

The next thing I'm trying to get squared away is my fuel pressure. It has an external FPR that sits between the fuel rail and the fuel pump. The FPR has a nipple that I assume is supposed to be connected to a vacuum source. Would connecting this to the inake vacuum lines work?

The FPR is definitely needing a vacuum hose connected to it for it to operate correctly.
Look for the original vacuum hose that went to the FPR, it may be lying loose, and connect it.
If there is no vacuum hose there, use a T fitting and 'T' a hose into a nearby vacuum hose and connect it to the FPR.
That should solve all your poor running problems, glad to hear that you swapped those connector plugs and it 'fixed' the flooding issue.
I had a feeling it may be a Engine Coolant Temp sensor problem.
Here's a couple of pics re the FPR taken out of my service manual.
This a 99 model, external pump and Reg and yours is a intank pump and reg but you get the general idea.

 

[Kiwi Rider]

Here's some more info on testing the coolant temp sensor

 

[Kiwi Rider]

The engine temp gauge on the dash is working off a separate sender unit which is located in the radiator..

Ok, this is incorrect, I just checked the service manual and the coolant temp gauge reading is coming from the coolant temp sensor via the ECU.
My bad, sorry about that, I work with cars a lot more than bikes lol!