Shutting fuel off whie driving.

[Walter Sherwin]

>>
>> >Flashing at this rate would not appear as constant.  However, the pulse
>> >width at idle would be so short that we might not even see it flicker.
In
>> >fact, the duty cycle will always be so low (12.5% max on 8 cyl) that the
>> LED
>> >will only ever appear dimly lit at best.
>> >
>> >
>>
>> When we talk duty cycle on any engine's injectors, is it the percentage
of
>> open time to time between intake events or percentage of open time to
closed
>> time regardless of RPM etc...
>> Reason I ask, is if my V6 is at 5200 RPM (see's it at least once a day!)
>> then it is running 5200/60/2 43.3 intake cycles per second or intake
events
>> every 23.1ms.  With a 23.1ms injector PW, that would be 100% duty cycle
>> correct?
>
>Yes.  duty cycle is always "on time" as a percentage of "on time" plus
>"off time".  The fact that it's a car, and there's some kind of intake
>event somewhere, does not bear on making duty cycle measurements.  the
>sum of on+off time does change with RPM, but the formula on/(on+off)
>doesn't change.
>
>--steve





Actually, no.    Ponder many of the late model SEFI's (LS1 for example), or
even some of the older OE stuff, and you'll see why.  The injector's duty
cycle is, by definition the "time that it is open versus the time that it
could be open".  Depending upon the software (OE or otherwise) this can be
drastically different than what you are portraying, or what is relevant to
the "Injector".  Injector duty cycle is not a durability "thing", it is a
control "thing".

Walt.