7747.

i see i am falling into it at idle when idle drops below 850 or so. the flag comes on and off in winaldl. i am running OL now so it is a non issue? other than richer than 14.7/1 in those cells. when in CL it is creating idle instability issues so i am OL for now.

now i understand the "static" concept. my motor should spin to 5800 rpms and i read/understand the tbi injector is static when it hits 5.0msec of on time. 85% duty cycle is 4.25 msec on time. i have a little more than 5.0 msec of time to open-close injector at 5800 rpms. with inj opening closing it appears i have enough time to prevent static. so WOT seems to be OK for me. all i need to do is add to the FP as i am 13.3/1 or so on WOT last i ran a log(s).

now back to idle. if i add to the FP for WOT it will create an overly rich idle. pretty certain that is not a biggie since my ign is up to task. so back to question. how does ECU recalculate the on-off time when asynch?. i assume it uses the nb02 feedback. does it just turn off injector pulse till it sees enleanment and at 14.7 and then turn it on again until it sees the overly rich condition at the 02 sensor? seems a better option exists.

please explain what is happening when in asynch.

 

What the ECM code does is to convert the Sync PW to an equivalent Async PW, to provide the same volume of fuel over time. The factoring for this conversion is from a 2D lookup table that is RPM based. The difference between sync fuel and async fuel is the rate, or frequency of injection pulses.

Sync being based on RPM, async being based on the code loop (every 12.5 msec).

The sync PW is the basis for fueling. This is always converted to an async PW. Then based on the min/max allowed sync PW the ECM will use one or the other.

RBob.

 

those tables are in 7747?

I don't see a 2D lookup table for async fuel in Tunerpro or Promgrammer for $58, but two parameters (constants) I found were min. and max. async pulse (locations: $036C and $036E). I guess these could be adjusted (aka: raise the min.async) for larger injectors. Or is there another fuel mod that people use for large injectors?