1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

916 916 Fuel Pump Doesn’t Stop Priming

Discussion in '748 / 916 / 996 / 998' started by Miika, Jul 6, 2020.

  1. I think you gave the answer yourself. Still got the old relay? Is the new conform spec? Good luck mate.
     
  2. Backwards fuel filter?
    Why was the old pump changed.
     
  3. No, the relay works normally.
     
  4. Yep still got the old ones and they do the same thing just keeps on priming. The new ones are same as the old ones.
     
  5. Filter is the right way and still if it wasnt it wouldnt keep priming. I thought the problem was the pump.
     
  6. The ECU runs the pump for a few seconds to prime the fuel system and make sure the pressure is there to start the engine. As soon as the engine starts and the ECU sees the motor running, then it runs the pump permanently. The 1.6 ecu bikes prime for a shorter time than the P7/P8 equipped bikes, but either way they should still stop after a short time.
    The 12V feed is provided off the injection relay to the pump, coils and injectors. The ECU then switches the earths on the individual components to make them run/work. It's also possible the wires feeding the pump assembly and fuel gauge have shorted and the feed for the fuel gauge is powering the pump? Pull the relay for instance and check if the pump still runs?
    It's not the easiest system to describe and testing out can be slow. Get a wiring diagram and go thru it carefully.
     
    • Useful Useful x 4
  7. Ill go thru the diagram next. Thanx for your advice! Ill keep you updated.
     
  8. Miika, try pulling the fuse for the indicators and idiot lights then switch on the ignition
     
  9. Ill try that out too:upyeah:
     
  10. Pulled the relay out and the pump went offline so the relay is working?
     
  11. Didnt helpo_O
     
  12. Yes, but it should only be energised for a short time, then drop out until the engine starts. Is the Ecu earth cable attached to one of the mounting rubbers? It’ll be a short black cable with a ring connector on it.
     
  13. Pump didnt prime at all when the relay was off and the earth cable was connected.
     
  14. What Nelly means is measure the current to the relay. It should be energised for a short period of time. If that’s oké you can move fwd. if not you can trace it the other way around.
     
  15. But isnt the ”+” current going to the relay and it should be energized all the time? Ecu controls the earth current and with that it operates differend things on bike. Or should i measure the earth current?
     
    • Agree Agree x 1
  16. The ECU switches the earths on the individual components to make them run/work. So yes.
     
  17. Yep:upyeah:
     
  18. Measured everything yesterday and it seems like the ecu is broken. Current from ecu to relay doesnt stop. I tried also with everthing off exept the components needed to be on when pump starts priming. I ordered new ecu so lets hope thats the issue here.:grinning:
     
    • Like Like x 2
    • Useful Useful x 1
  19. It looks like the only culprit left, at least you've done your best to eliminate everything else, hope the ecu sorts it.
    Steve
     
  20. Is the eprom in the correct way round?
     
    • Agree Agree x 1
Do Not Sell My Personal Information