My 916 dosen’t stop priming the fuel pump. No matter how long i let it prime it just makes the constant priming sound and never stop. Priming should stop about 3-4 second into putting kill switch on run. Everything with the fuel pump and fuel system should be working. Is the problem then in ECU?
Good chance there could be a split in the fuel pipe in the tank, undo the fuel cap and look inside for movement.
Cant be because i just putted a new pump in and all the hoses are new too and i checked every thing from the hoses to regulator aswell.
+1 for Birdie’s suggestion ^^. Sounds like there’s no pressure building to tell the pump ‘we’re good bro, you done you’re job, for now’
It’s a PITA but if it were me I’d be pulling out the whole assembly again and rechecking; A) everything is plumbed in correctly ie the correct hose to the correct place, and, B) all connections are tight & secure.
Just opend it after trying again and everything looked normal and snug fitting. Does the ecu have a program for the priming?
I may be wrong but I always thought it was a pressure switch in the fuel pump assembly that causes the pump to switch on/off as needed . I don’t think pressure readings are fed back to the ECU
So you are saying that the pump should know by itself when the pressure is good? So it would measure the pressure from the returning hose or something?
That’s my understsnding of how fuel pumps work and I’m not sure why Ducati, or any manufacturer, would over complicate the matter. However, it would really need someone with direct knowledge to confirm, perhaps @nelly or @Derek may know.
There is no " tell back " from the fuel system to the ecu . It runs the pump for a few seconds then stops . Once the engine is fired-up , the ecu runs the pump continuously . I'd be asking myself why the ecu "thinks" that the engine is running when it isn't .
The pump has no way of sensing when pressure is "good" and the pressure regulator is a purely mechanical device .... a waste-gate to protect against over pressure . There should only be 4 wires coming out of the tank .... 2 go to the pump and 2 go to the fuel level sensor
Useful so there’s no internal pressure switch in the pump then? The pump just runs for a predetermined time at ignition on until the engine is running at which point it then runs continuously? @Miika I did say I was assuming things, I’m glad Oldtech jumped in
When i try to start it nothing happens. There is no fuel going in cylinders and no spark at all. But i was thinking that ecu would’t let fuel go into cylinders and the sprkplugs wouldn’t spark if the fuel pump hasn’t finished the priming. Could i be on a right track with that?
