Understanding Injector Duty Cycle

[JulianSerna]

Hi,

I am trying to make a full transition from a PMS ECC to my new AEM 30-1401 and am not fully understanding how injector duty cycle is tuned here. My point of confusion comes from the fact that AEMPro allows me to input values greater than 100 % duty cycle (raw 255 max) and from what little I do understand, 100 % duty cycle means that the injector is constanly ON, so what does it mean when I see tunes with fuel map cells greater than one hundred percent?

Thank you in advance,
Julian Serna

[toyman]

Hi,

I am trying to make a full transition from a PMS ECC to my new AEM 30-1401 and am not fully understanding how injector duty cycle is tuned here. My point of confusion comes from the fact that AEMPro allows me to input values greater than 100 % duty cycle (raw 255 max) and from what little I do understand, 100 % duty cycle means that the injector is constanly ON, so what does it mean when I see tunes with fuel map cells greater than one hundred percent?

Thank you in advance,
Julian Serna

There is a separate view for duty cycle. I have no clue as to what the raw view represents. My tune was done in the pulse width view. If I look at it in duty cycle view there is nothing over 96% and in  raw 157 (?) something is the max.

[JulianSerna]

Just spoke to AEM Technical Support and they said that basically you should never have anything over 100% duty cycle as, technically speaking, it is impossible to have the injetor opened more than 100% of the time. It is like saying someone is working 25 hours per day when there are only 24 hours in a day!

He said, however, that they cannot go back and modify the firmware to prevent this so they left it just like that, but anything over 100% duty cycle is the same as 100%, period.

[trbo2dr]

the ems has staged injection capabilities so when you see idc's greater than 100% it usually because you have secondary injectors.  there is a table that specifies how much and at what point the secondaries inject.  take a look at the mazda rotary base cal for an example.