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F800 won't start - the ongoing saga

tasslehawf

New member
2007 F800S. I haven't ridden it much if at all in the last 2 years. Wanted to sell it, but wanted to do the idle hose mod first and never got around to it. Finally decided to just get it inspected and get it out, but now it won't start.

I figured it had to be fuel issue since it basically always started, but not since it sat. Drained the tank and put in new gas. When I pulled the fuel pump assembly out of the gas tank, the fuel screen was completely disintegrated. I'm afraid that some of the plastic debris may have been sucked into the pump, not sure if that is the issue or not.

Here's the issue: when I try to start the bike it doesn't. If I use starter fluid, it will start but die after a couple seconds. Now this is what I want to know -> If I put my GS-911 on the CAN port, it tells me that the fuel pump is OFF and the fuel pressure in about 14.5 PSI. Considering that I had the fuel line disconnected from the fuel pump (I wanted to see if it was spitting out debris), the pressure is puzzling, but I'm really curious about the fuel pump. It doesn't make sense to me that the fuel pump would be off when you start the bike.

Thoughts? I'm assuming that my next step is to replace the pump. Do I also need to replace the controller?
 
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I reset the fault codes and I watched the fuel pump come on then immediately shut off with the diagnostic tool telling me that the fuel pump had tripped its fuse. So fuel pump is definitely not happy.
 
Sounds like you are on the right track with this problem. The only thing I can add is that I use aerosol GumOut as starting fluid. Less volatile, less cylinder wash and does the same job.
I don't know how the fuel pump is controlled on that bike......On others, the FPC has been a problem. There is a Best of Forum on FPC's.
Let us know how you make out.
OM
 
The fuel pump appears to be dead. The controller seems to be OK, although I'm tempted to replace it with the updated one anyway.
 
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