hello and thank you to anyone who cares to read and give feedback in this thread. i just got an an 03 evo and started logging the car and have noticed a few things which i would like to get straightened out.

Category 1: evoscan not logging or incorrectly logging certain parameters

a. not logging 2 byte load--both evoscan and my rom have been updated with code to log it
b. wgdc%--defaults to either 80% or 100% when in vacuum and then finally changes to appropriate percentage after i hit boost (not sure if i have to update my rom but i dont believe so, only EvoScan data.xml file has code in it)

NOTE: these things worked when i was logging my previous car


Category 2: My MID fuel trims look weird, they are a lot higher than low or high trims, is that possible? I thought that trims should be highest in short term and get smaller through mid and high?

I am attaching my latest log file as well as my injector settings, latencies, etc (i am running denso 720cc)

I appreciate your help




thank you

 

Double check the code for the 2-byte. Make sure the requests in the EvoScan formula correctly match the locations in the MUT table.

Depending on the year model and ROM, some will default to 0 WGDC and some to 100 WGDC. If it's working while in boost and above 2500 RPM it will be fine.

Low, Mid and High trims are all LTFTs. They reference different airflow ranges ... something like:

Low - 0 - 100 Hz
Mid - 100 - 500 Hz
High - 500 Hz +

So, yes. They can be quite different and larger injectors are usually the cause. If your injector latency values aren't correct the trims will move further apart. The tuning process is:

Set scaling value to get mid trims in check
adjust latency to get low trim closer to mid

You can read the specifics in the how to tune an Evo thread or one of the many injector scaling threads.

Hope this helps.

 

1 question, why are using ver. .99 when the latest release is 2.*?

 

I personally use .99 as well because I have no use for the additions in 2.x. I have them all from .99 up but never use them. My XML in .99 is just how I like it and it's never failed me.

 

same here, dont fix whats not broke, well its broke in my case hence trying to fix it

 

i appreciate your help, seen many threads on fuel trims, injector scaling and latency adjustments etc, do you have one where a nice comprehensive summary of methodology is written? not being lazy just went through several of them and havent found anything that truly resonated with me

 

Me either ... lol. It really is sort of a theoretical process until you try it yourself. You really can't completely grasp it until you try it yourself. The "How to Tune an Evo" sticky has some good info though.

These are the basics ...

Start by scaling the injector size to about 13% to 16% below actual size.
Rough-in the latency using known values (https://www.evolutionm.net/forums/sh...5&postcount=51). If your injectors aren't listed here, guestimate based on a similar injector.
Go for a drive and take it easy ... at least 20 minutes of cruising out of boost.
Check your fuel trims.
If mid trim is + then the ECU is adding fuel. This means the injector scaling is too high. - trims mean pulling fuel or scaling too low.
Change scaling, reflash (and pull battery cable to reset trims on VIII)
Cruise some more and repeat till the mid trims are within about 6% or so.
Once mid trims are correct you can adjust latencies until the low trim gets in line with the mid.

 

so if you look at my map the mid fuel trim is negative (-9.9%) so with my 720 scaled to 636, i should bump the value up?

also say if my trims were good, if i start messing with with my afr map, and start leaning out the afrs in cruising cells, would that cause the - values to go up on the trims meaning the ecu was pulling fuel?

Thanks

 

Yes ... if trims are -9.9%, I'd increment the scaling value up twice (+ +).

Leaning the fuel map has no effect on the trims since the trims only affect closed loop fueling and the map only open loop.

 

last question, when logging trims after resetting battery, can i do it even if i am in open loop or should it be done in closed loop ?

i am in open loop as i changed my open loop load to increase afr in cruising conditions

thanks

 

Trims will not change in open loop, so no, you can't correctly scale the injectors with the open loop cruise mods. Watch the O2 Feedback value ... if it's static at 0% the trims aren't in play.

Also, you don't need to pull the battery cable on a IX since the trims reset when you flash.

 

thank you