Hello all Curious if anyone has experience with a delay in the fuel pump priming? Once I turn on the ignition on my 2000 996, there is a long delay before the fuel pump will prime and the bike won’t turn over until it has done the priming. Pressing the start switch does nothing until the pump has primed which the time varies. I should add that it always eventually does prime without any intervention from me. Sometimes it takes 10 seconds, sometimes 30 or more seconds. It seems to do this after sitting for some time. Once the bike is running and I shut off the ignition and turn it back on right away the fuel pump kicks in right away. Any ideas what could be the cause? Thanks in advance!
it could be a sticky fuel pump, I have had various issues with fuel pumps when my bike has been standing for a while but it will usually pump or not if it is really stuck. The best thing to do would be to take the pump out of the tank and test it, if it spins immediately then the pump is good and you can always give it a clean. If it's slow to spin then there could be some minor gumming up or some other problem that is causing the delay. If the pump proves to be good then it's likely it's an electrical fault. If you connect the fuel pump the wrong way it spins in reverse, I have used this method to free a slightly sticky pump by constantly reversing the connections and rocking the pump effectively backwards and forwards. Finally, I have also freed a sticking pump by taking it out and using carb. cleaner in the pickup and discharge points in the pump. Is your fuel tank clean as rust could be causing petrol to not reach the pump and you may not hear it priming.
At switch on the ECU will energise the fuel pump relay for about 2-3 seconds the switch off. If the pump hasn't primed within this time then it's not going to. Nor should the fuel pump priming or not affect the operation of the starter. I think the problem lies further up the line with the delay being when the ECU gets powered. Perhaps, more likely, the injection relay sticking?
