A little dazzled when speaking about injector offset. The section of setting up injectors was thoroughly read several times
in the help contents of the software, but not much information was analyzed in order for me to figure out if Injector offset should
be set right in the process of creating a basemap, or during the first startup of tuning a car.

If so, am I suppose to convert 990 ultra seconds to milliseconds and input that number in the offset table, since eCtune
displays units of MS regarding offset during regular charging idle, or use the standard regular 12 volt battery
voltage linear to 43.5 psi of fuel pressure?

 

Use the row that corresponds to whatever your base fuel pressure is...then move across.

usec is "microseconds"

to convert to millisecond divide that number by 1000 or simply move the decimal point three spaces to the left.

for example, 3015 microseconds = 3.015 milliseconds

 

Understood, but based on regular charging voltage(14 volts, no electrical loads
applied, engine idling), my guess is that I should be running around 990 "microseconds"
for that particular time until I get a steady stoich fuel ratio(14.5-14.8) by manual fuel
value adjustments in the low cam fuel table, correct ?

Then once my fully warmed up primary AFR's targeted at stoich, go in and adjust inj offset
based on batt voltage through hardware settings inside the parmeters window. Correct ?

I am using eCtune as my software atm.

 

Don't overthink it.. Just put the battery tables in, and give the motor what it wants in the fuel table to run properly. The stock ECU is a vary old outdated and far from precise method of engine control.. The values in the fuel tables are of very little relevance so long as the engine runs properly.

 

Sorry to break this down to you based upon the experience with my car; but the car had
no potential what's so ever to even see base idle during cold start or warm starts if
the values your talking about in the low cam fuel weren't adjusted to a proper certain
number. Your saying they are absolutely irrelevant I'm not running stock injectors, I am
running I.D's 1000 @ 43.5 PSI of FP. The Values on my low cam fuel map were calling
for adjustments, because at actual startup the motor had no potential to idle what's so ever.

 

You have to enter the new injector size in the injector multiplier table.. This will get you close enough to crank and idle the car. From that point on you adjust the main fuel table. Put the battery offsets for your pressure in, and put 890cc in the main injector multiplier table and it'll start.. Work your way from there.

 

I still can't believe why the software didn't accommodate for the re-adjusted current injectors that I have set up when creating a basemap in the prologue of the tuning process. Perhaps the overall trim(final fuel multiplier) didn't add enough fuel because my input for current injector size was wrong ?

Right now it's making me really anxious and worried because I think I have blown a head gasket trying to mess around with the timing just to get it idling before I even knew all about this.

When I had no idea about all of this, here's the beginning side of the story as to what happened ...

I was too scared to raise the idle, but at one specific point the car died out because I thought timing was the issue. Following my buddies ideas, who for some reason had great success with a megasquirt standalone, tuning his miata, I advanced the timing to be set at around 13.00 BTDC going across the horizontal rows/columns right before boost at about 500 to 800 RPM. (Here is the stock non adjusted picture for reference that I used later on to crank the car which significantly showed improvement, and I think I should've just stuck to that!!) Sorry that I am making this more confusing than it already seems.



In Addition, the low fuel values already pre-assigned to the low cam fuel map by default when the basemap was created had to be the main restriction as to why the car didn't want to start in the first place.

After figuring it all out after about 4-5 hours of messing around with it, I am hopefully hoping to god that nothing more than a blown head gasket was brought to the massacre table through these inexperienced hands by trial and error. For the car to have the potential to even idle at a steady 700-800 RPM, I noticed that the fuel units had to be increased like so...



opposed to the "DEFAULT" Settings...



Starting the car at a fully warmed up temperature(210*) is another problem that I experienced. When I ran the adjusted fuel map for cranking during a cold start. It seemed the car had no problems starting when the 500 RPM row right before boost(which im guessing is cranking) was adjusted like so ...



Maybe I'm missing out on something here with IAT enrichments, or Warm up enrichments, but I really don't have a clue. Sad.

 

So wait a minute bugermass,

your saying that the injector flow rating for the I.D 1000's is 890CC instead of 1000CC ?

When I do that inside parameters, the Injector(final)multiplier increases from .240 to .270. Perhaps it will have a better time starting right now without having to manually increase the idle units inside the low cam fuel table like I was doing before ?

 

Yup give it a shot. Also i usually end up adding anywhere from 10-20 FV Offset .. U may wanna take the car to an experienced tuner if you are unsure what to do. It may save you time and stress..

 

Well I kinda wanted to learn it myself :/ ... But I know what you mean. Hell I have all the time in the world to learn this kinda stuff. I don't mind at all.

 

But hey, believe it or not whatever you have just covered in your posts regarding injector offset, and how to calibrate a good afr for proper idle is already stamped in my head. The only thing that confused me based upon the efi knowledge is why I have to change the flow rating from 1000cc to 890cc?

 

The math in the ECU isn't 100% correct, as well as IDs are flow tested slightly differently than all other injectors. So in relation to the older ECU its a bit closer to 890-900CC...

 

Okay, that makes sense. Now I should have a slightly little lower LEAN AFR than what I had before to when I was trying to crank the car. Now it makes a hell of a lot of sense why the multiplier table increases when I change the flow rating from 1000cc to 890cc..

 

Still continuing to experience problems with cranking the car on a default basemap, even though the injector flow rating has been adjusted to 890cc. None of the parameters have been touched, as far as crank trim, post start trim, etc. Overall fuel trim is ofcourse adjusted in calibration tool once I get the car to idle by the help of manually fixing the fuel table values during a proper respected idling car on a p72 map.

Just replaced my headgasket about 2-3 days ago on the weekend, when I had time.

Due to a little bit of off-time, because of my 8 to 6 wrenching job. >_<

.. I create a basemap, on 890cc for new Injector flow rating(Like you stated Bugermass), and on a very stone cold start, this is what the new fuel values are, when adjusted from the actualy default p72 settings on a 890cc flow rating setup for my ID's.



If you compare the picture above(1000cc) flow rating with the one in this post, I have lowered the fuel values by a lot. Maybe I should lower the flow rating down to 770-790cc, and see what happens from there, with the default gsr basemap. It seems like the car has a much better chance starting, since the fuel multiplier has jumped quiet the gun in parameters.

Any inputs ? :/ I know I'm getting closer to the bone, I just don't want to go through anymore internal failure. please help..