The EFI system is disappointing me
#111
Since this thread started out by stating that the OP's bike ran well during warm weather, then performance took a dive during a drop in temperature - is this or is it not counter intuitive? My understanding [and confirmed experience] is that any internal combustion engine runs MUCH better in colder, denser air. Is my understanding incorrect?
#112
Open loop still uses the MAP and Temp sensors to adjust. It just doesn't have that "loop" that is controlled by the o2 sensors for the cruising area that most riders are in 90% of the time that will be adjusted to stoich.
#113
I'm not sure I understand your point here. Are you saying that the o2 and temp sensors are not being used to adjust fuel mixture above idle in a closed loop system?
#114
google "speed-density tuning" then you will understand.
Why do you think they have temperature and pressure sensor?
The ecm is measuring the density of the air. Once they get the density of the air they can then get the mass of the air. Once they know the mass of the air they can calculate the mass of the fuel required using the AFR programmed in the relevant cell. Or if closed loop a constant 14.6 AFR
(I am sorry that I know all this stuff, but once a bell is rung you cannot unring it)
Last edited by MikerR1; 10-25-2016 at 11:31 AM.
#115
How does knowing the pressure in the fuel system measure air density?
#116
keith, I will let someone else explain it to you. The MAP sensor is not measuring fuel pressure.
#117
I am saying that an open loop system makes all the same adjustments for elevation and temperature that a closed loop system does. It seemed in your statement that you implied that only a closed loop system would do that.
#118
Oh. No. I was only talking about a closed loop system. But, thanks for the clarification.
#119
google "speed-density tuning" then you will understand.
Why do you think they have temperature and pressure sensor?
The ecm is measuring the density of the air. Once they get the density of the air they can then get the mass of the air. Once they know the mass of the air they can calculate the mass of the fuel required using the AFR programmed in the relevant cell. Or if closed loop a constant 14.6 AFR
(I am sorry that I know all this stuff, but once a bell is rung you cannot unring it)
Why do you think they have temperature and pressure sensor?
The ecm is measuring the density of the air. Once they get the density of the air they can then get the mass of the air. Once they know the mass of the air they can calculate the mass of the fuel required using the AFR programmed in the relevant cell. Or if closed loop a constant 14.6 AFR
(I am sorry that I know all this stuff, but once a bell is rung you cannot unring it)
#120
I did not say they had a mass air sensor. They have a MAP sensor. They calculate the density of the air and from that they can calculate the mass of the air.