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Yep
Suffice to say start it up. Sidestand down idling if there is a code it'll start flashing the FI light. The manual tells you how to read the flashes and what they mean. Let us know what you find out and we'll go from there.
 

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Discussion Starter #22
Yep
Suffice to say start it up. Sidestand down idling if there is a code it'll start flashing the FI light. The manual tells you how to read the flashes and what they mean. Let us know what you find out and we'll go from there.
OK. Thanks
 

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Discussion Starter #23
Tried the idle on the stand thing and the light doesn't glow at all. Will keep digging.
 

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You may find that it isn’t a hard fault, so the diagnostic light won’t come if the fault isnt ‘active’
In that case , You will need to jumper out the service connector and then watch & record the faults indicated on the FI light.
Just my 2c , as I’ve had a similar issue in the last week myself
 

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Discussion Starter #25
OK. There is definitely no flash of the FI light when running with the stand down. If I short the service connector, it flashes 8 times. I believe this means the throttle position sensor has been faulty, but it isn't now?
 

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I had exactly the same issue. So I have cleared the ECU faults and been for 2 decent rides since , with no fault codes thrown since. As they say it typically won’t be the TPS , it may be wiring to the TPS.
 

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Discussion Starter #27
Just tested the fuel delivery. 35 PSI and flow is ok. Will try to set up the gauge and a volt meter so I can ride it. Starting to think there is a fuel pump and/or regulator issue.
 

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Shed
Agree with Aaron, once you have cleared the fault I'd run it and see if it acts up again. Then recheck the codes. If the TPS comes back then that would explain the symptoms your experiencing. Was going to say the bike was/is going into a limp home mode. When you power cycle it the system resets.
So first order business take it out and see if it triggers again. Check the code and then go from there.
 

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Discussion Starter #31
Minor update - havent ridden it yet, but one thing it does do is stall when cold. My CB400 idles up to 2000 when cold. The Bird is very sluggish and struggles to idle at 1000 cold. Not sure if its it related.
 

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Discussion Starter #32
Update
So, rest the ECU memory and took the Bird for a long ride with a volt meter and fuel pressure gauge.
Volts are rock solid so we can rule that out. Fuel pressure ranged from 35 to 27 when under load.
On return, there are no faults in the ECU, and it behaved well all the ride. Except start up from cold. It needs throttle to kick it to life, and then the first few 1km or so it runs like a dog.
So, the ECU reset has fixed the issue, and as beestoys pointed out, it must have been going into a limp mode.
So, thinking it needs a fuel pump, filter, and regulator. Thoughts?


129445
 

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Manual calls for 50 psi so your bike is at half pressure under load. I would start with a pump/filter. Clean up that connector as well.
Side note: If you use Partzilla, prepare to wait 4-5 weeks for your parts.
Edit: Would you show how the pressure gauge is set up if possible? Thanx.
 

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Discussion Starter #34
I have a fuel pressure test kit with a range of fittings. I screwed it into the drain/tapping point at the fuel tank (small screw at the banjo fitting).
 

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Agree with excellent. You need to see 50 psi head against the rail with the key on engine off. It should go to pressure and hold it for at least a minute or 2. If your not then do a test deadheading at the pump itself no rail. If it's not check the above as he states. If it's good then your rail is dropping pressure. Either FPR or injectors. as above verify input side is clear if obstruction. If it's not then pump is leaking by internally. Time to replace.
 
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Discussion Starter #36
Agree with excellent. You need to see 50 psi head against the rail with the key on engine off. It should go to pressure and hold it for at least a minute or 2. If your not then do a test deadheading at the pump itself no rail. If it's not check the above as he states. If it's good then your rail is dropping pressure. Either FPR or injectors. as above verify input side is clear if obstruction. If it's not then pump is leaking by internally. Time to replace.
OK. Thanks
 

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Discussion Starter #37
I took off the bypass hose from the pressure reg. No fuel comes out with the pump running.
I blocked the delivery hose to the rail, and it peaks at 35PSI like it did running at no load.
Looks like the pump/filter combo is struggling, and the regulator might be ok. Will pull out the filter and pump.
Thanks
 

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There is another test, fuel flow rate. Of hand, I don't know what it should be, its in the factory manual somewhere on this site. Measure the amount of fuel flowing into a container over set amount of time. Pump/filter must pass both tests to be good, looks like yours has already failed one anyway.
 

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Agree with Fizzy. Pull the filter assembly and try running the pump pickup with an extension no filter to rule the filter out. It doesn't take much restriction on the inlet side to kill the output. It'll also give you proof it's a filter issue.
 

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Discussion Starter #40
Agree with Fizzy. Pull the filter assembly and try running the pump pickup with an extension no filter to rule the filter out. It doesn't take much restriction on the inlet side to kill the output. It'll also give you proof it's a filter issue.
Will do. Thanks.
 
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