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jl135w7

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Jul 26, 2024
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Florida
Bike was running ok about 8 months ago. Had a sputter when trying to hard accelerate. Bike sat for 8 months. Started up but was rough idling and you couldn't ride it because it would die. Figured I would go full clean on it. Almost. Did new plugs, fuel injectors cleaned at shop. Flow is good pattern is good. Tank was about empty the entire time it sat. Added almost half a tank of new fuel and started it. Same issue. Idles bad then died. For some reason I started it while the tank was propped up. It ran started and ran!!!!! Put the tank down and it died. Thought maybe the fuel pump was weak because it worked with the tank up. Maybe the angle of the fuel flowing through the hoses helped it run. Ordered a replacement pump and strainer. Pulled the fuel pump housing our ofnthe tank and replaced the pump and strainer. Tank up runs. Tank down dies. Thought maybe the fuel line was collapsed inside. So I bought a fuel line from napa. Cut it and clamped it on to see if that was the issue. Tank up runs. Tank down dies. The tank does have some rust in it but what tank doesn't in Florida. The only thing I know that's left is the fuel pressure regulator on the fuel rail feeding back into the tank. Not sure how that would cause the bike to die when the tank is down vs being up. My car engine died and this has to run asap or i dont have a car. Any and all help is appreciated guys. Oooo it's a 2004 fjr. 40k miles.
 
Water in tank? It does sound like some contamination under the fuel, lifting tank will put the fuel pick-up higher in whatever liquid is in there.

Drain tank completely, put in fresh fuel.
 
Does it run well with the filler cap open? If the problem goes away then the pinched vent or clogged filler neck is probable, otherwise it is very likely to be debris, water or some other contaminate in the tank. It is easy to siphon off some of the tank contents with a hose as far down into the tank as possible. Siphon it into a clear glass container and you might see the problem.
 
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