The pump and coils have power at all times unless they are interrupted by safety protocol. This means that if the ECU shuts off the pump it kills the coils at the same time. Once the fuel pressure is reached the pump shuts off. When the injectors are operated, fuel pressure drops and the pump pressure regulator allows current to flow. Voltage is constantly present. So although current is zero at the pump the potential is always present unless the key, kill switch, or safety tells the ECU to open the relay to the fuel pump and ignition coils.
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I hear you but I don't agree on all points.
The pump and coils have power at all times unless they are interrupted by safety protocol. This means that if the ECU shuts off the pump it kills the coils at the same time.
Mostly agree. There is the safety protocol for shut down but based upon some testing I did, I think it may time out and wait for the crank to spin to conserve energy. Its just ones and zeros in the ECU (digital realm) so this is possible.
Using the same logic, its not going to squirt fuel on an engine thats not being rotated, so why power the injectors at all. Point: we have fuel pressure, now lets wait for the crank to spin - whether from the button or rolling it down a hill, we wait until movement is detected at the crankshaft and then TURN THE Injector/Pump again!
Once the fuel pressure is reached the pump shuts off. When the injectors are operated, fuel pressure drops and the pump pressure regulator allows current to flow.
The pressure regulator is just an overpressure dump valve. If pump pressure exceeds the springs rating, fuel is dumped inside the tank and pressure drops before the pump stalls (current gets too high).
- So, the ECU could detect current or voltage and sense the pumps load, but it has no idea of the pumps/fuel rail pressure. There is no pressure sensor on the pressure side of the pump.
IDK! I've never measured it. Its possible. It all depends what they used (circuit; IC/logic dependent) as to the outcome. That said; the fuel and ignition are separate (sorta). The black box does some magic. All we know is if we want it off now, the RED switch kills power to the ignition coils and it stops, even if the ecm is giving the green light to keep on keeping on...Voltage is constantly present. So although current is zero at the pump the potential is always present unless the key, kill switch, or safety tells the ECU to open the relay to the fuel pump and ignition coils.
If I were to measure it, I'll hedge my bet that there is no need to power the injectors if the crank is not spinning. It is the ONE sensor that STOPS the bike dead in its tracks if the signal is not proper or present. Most others have fail safe defaults that allow limp home in crippled fashion.
IMO - there is no reason to power the injectors if the engine is not rotating. So, digital logic being what it is, its pretty easy to turn off the injectors and wait for the crank to spin. How long is the question!
Based upon my own experience where I removed the fuel tank which allowed air into the fuel system, I believe the processor is checking the load on the pump as "pump on times" can vary.
That's my best guess! But we could beat it with a Hamster because its electrical! Blah