Originally Posted by tkklemann

The latency accomodates differences in Voltage between car to car. It's not really dependent on RPM (At least at Idle. Voltage goes up a little with RPM's though. But, for the purpose of dialing in fuel trims (Specifically idle) you will be concerned mostly with the voltage your car is seeing under idle conditions).

What you need to do is log at idle what voltage your car is running at, and adjust the value closest to that voltage. (Assuming your Injector scaling is close to where it should be) Most of the time, you will be changing the 14.0625 voltage, but changes in the "surrounding voltages" 16.4062 and 11.7188 will also have effects, but not as great as the 14.0.625 voltage. Here is a condensed blurb from Razorlab I believe (Maybe someone else) on adjusting Injector scaling and latencies that I reference occasionally:


1. Choose an ECUFlash injector scaling number
2. Log trims at idle and cruise
3. If trims are roughly the same, but positive, then you need to lower your injector scaling number.
4. If trims are roughly the same, but negative, then you need to raise your injector scaling number.
5. If idle trim is more than cruise trim, then increase the dead time by increase the latency value.
6. If idle trim is less than the cruise trim, then decrease the dead time by decreasing the latency value.

Originally Posted by senate6268

Here's the basic rundown of what your approach should be:

Originally Posted by 03lances

Your idle is more than you cruise so you will want to increase the latency, then you will end up having to increase your scaling as well


o not to steal your thread jrr but for some reason my car wont register idle trims at idle?? If I cruise in 4th about 30mph it will change the idle trims

Originally Posted by JRR

ok so it looks like my trims are:

low .1008
mid range -7.351 to -10.0964
hi .1008


now to adjust. but which way to go?


josh

Originally Posted by 03lances

Something is off here because increasing the latencys with these trims would have dropped the mid down even more and then dropped the low by approx. twice whatever it dropped the mid bringing the two closer in relation, then raising your scaling would have brought both numbers back up closer to 0, Correct? Or am I confused Unless your low trim was not actually .1008 (this is the exact number evoscan will show as the 02 sensor feedback if there is actually no signal) This was actually part of my issue with the 05 ecu is the 02 sensor feedback was frozen with .1008

latency increase= more fuel, approx 2x more at idle than cruise
scaling increase=less fuel, same amount at idle and cruise

Unless I am mistaken about what I have read

Originally Posted by JRR

well im not actually running a front 02 sensor. i have a dummy signal coming over from my wb to give it information.


josh

Originally Posted by 03lances

Oh thats interesting so your wb is in your 02 housing? dont they reccomend like 36" from the turbo or something like that? How exactly does that work since the front is a narrowband? Are you constently in open loop or something?

Originally Posted by 03lances

In the latency map are you adding a full 2 points or .2? A little goes a long way there. If your using the increment decrement keys don't do this for latencys manually enter them .1 at a time that's what I do works good for me.

Originally Posted by 03lances

I am at work right now but when I get off I will post my latencys. I am running the stock 03 evo maf values as senate posted in the maf swap thread.
You removed your 5th injector and running 440s correct? I have mine scaled to 412 right now which seems alright.