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Backfire, won't start, Fatbob, please Help

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Old May 26, 2019 | 07:28 AM
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Question Backfire, won't start, Fatbob, please Help

Hello, i am new to this forum , i am here to ask for help for my 09 Fatbob

So , i own a 2009 HD Dyna Fatbob fuel injected bike , everything was fine until one day it had trouble starting , it started but was misfiring with black smoke. Then a couple of days later , when i want to start it, it just cranks and misfires.

I read here on the forum that it might be the coil or the crank case sensor ( i got error p0373 )
I changed the the coils and the crankcase sensor, still the same problem . Now what ?

just wanted to mention , the bike is stored in my garage so no water problems , i checked the ground wires, and the wires coming from the crackcase sensor to my ECU.

Any information will be useful .
 
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Old May 26, 2019 | 12:05 PM
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How old is the battery? Get it fully charged and load tested.
Possible leak in the fuel line inside the tank.
Do you still get the code?
 
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Old May 26, 2019 | 12:17 PM
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i bought the battery this year and have it fully charged , i will try another battery tomorrow, i just checked the lines in the tank with flashlight and they seem OK .

Also , i have new plugs ( tried to start with the old ones as well )

I have no error codes.
 
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Old May 26, 2019 | 12:21 PM
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Don't try another battery until you have your load tested. Even if it shows full charge at rest, it doesn't mean it has enough under load.
 
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Old May 26, 2019 | 12:29 PM
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So , battery voltage
12.6v sitting
12.3v ignition on ( and lights)
9.5v ( lowest) when cranking

it misfires and black puf of smoke comes out the exhaust
 
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Old May 26, 2019 | 12:59 PM
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below 10 under crank is considered bad.
do as mr. nevil suggested, charge and do two back to back load tests, first is to remove and surface charge and second to see what is going on.
if coil saturation is low, the output will be low so you will get a weak spark. if the cyl loads up with fuel, it will smoke black and hard to start.
 
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Old May 27, 2019 | 09:18 AM
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I tried with my car battery , same problem , so it's not the battery.

Any other ideas ? anything would be useful
 
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Old May 27, 2019 | 07:22 PM
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Are the plugs wet?
 
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Old May 27, 2019 | 07:39 PM
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You said you stored it in your garage. My question, how long had the bike sat without being run?
 
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Old May 28, 2019 | 12:57 AM
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The bike was sitting about 4 months , and the symptoms came gradually , it started harder and harder , now it will not start at all .

@Max Headflow, no , no water issues.
 
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