60lb Inj. Problem

[my_bd]

SJSchafer, did you obtain per-injector data from Yaw Power?

I had my injectors cleaned and dynamically tested by Yaw sometime around the end of last Oct. / beginning of Nov., back when he was initially developing the testing method for the LSJ's.
I did not receive per-injector data, but what appears to be an average of the set (I guess?).

Attached is a screencap of the low pulse adder behaviour for my injectors (Siemens Deka 60's).

Paul did mention during a discussion that he was quite impressed with the consistent behaviour he was seeing with the SD60's he was testing.

[4.8t]

you don't have that in numbers do ya? or maybe post a tune? please

[SJSchafer]

SJSchafer, did you obtain per-injector data from Yaw Power?

I had my injectors cleaned and dynamically tested by Yaw sometime around the end of last Oct. / beginning of Nov., back when he was initially developing the testing method for the LSJ's.
I did not receive per-injector data, but what appears to be an average of the set (I guess?).

Attached is a screencap of the low pulse adder behaviour for my injectors (Siemens Deka 60's).

Paul did mention during a discussion that he was quite impressed with the consistent behaviour he was seeing with the SD60's he was testing.

That graph looks very similar to what mine were. The only problem is that with the adders he gave me, while I am sure they are what's needed to have the injectors run linearly, they do not let the injectors pulse low enough for my little mouse engine, so I have had to "adapt" them to make them work on my engine with a returnless system. You care to send yours and I'll send mine and we can compair?

[4.8t]

ok so i've been messing around with the adders. when the tahoe is bone cold it idle WAY lean. then after about 20-30 seconds the stft start to add fuel. then it richens up but it don't stop at 14.7 it keeps going and going till like 13.9. so i have fuel trims of like +25 and a idle of 13.9. why won't it do like trims of say 19 and stop at 14.7? why does it keep adding fuel? drving around it does ok but still have trims of 9-10 but at least they are in the 14.5ish range.

[SJSchafer]

ok so i've been messing around with the adders. when the tahoe is bone cold it idle WAY lean. then after about 20-30 seconds the stft start to add fuel. then it richens up but it don't stop at 14.7 it keeps going and going till like 13.9. so i have fuel trims of like +25 and a idle of 13.9. why won't it do like trims of say 19 and stop at 14.7? why does it keep adding fuel? drving around it does ok but still have trims of 9-10 but at least they are in the 14.5ish range.

What's your commanded when idling at 13.9? By the way, the chances of you getting anywhere tuning adders in CL are slim. I mean, I suppose it's possible, but I don't really see how. With the trims going, the PWs are all over the place. Man that would drive me nuts!

edit = changed "OL" to "CL". Sorry 'bout the typo...

[my_bd]

That graph looks very similar to what mine were. The only problem is that with the adders he gave me, while I am sure they are what's needed to have the injectors run linearly, they do not let the injectors pulse low enough for my little mouse engine, so I have had to "adapt" them to make them work on my engine with a returnless system. You care to send yours and I'll send mine and we can compair?

yeah same issue here, I have one of those mousey lil LSJ's too with the high rail pressure all the time.
I had to scale down the adders to get the idle and decel under control.

[4.8t]

commanded at idle is 14.68. i hit the fuel trims off button and still idle at 13.9ish. i am logging adverage pulse width and it won't go below 1.7 and at 1.7 it can range from 15:1 afr to 13.5:1 afr. how is this? what am i missing here?

i also tried turning off the fuel trims while logging and useing RTT to mess around with the maf and i could make it go richer but not leaner than 13.8-14.0 afr

[4.8t]

lol - of course I have some numbers for my injectors, I paid to get them!
I dunno man, I don't think Paul Yaw at Yaw Power would really appreciate his hard work getting distributed all over the place, afterall he is trying to run a business and make a living.
I think dynamic flow data for your injectors ought to be slightly different from mine.

well you said you had to scale the adders down to get the idle and decel under control so technically there not the numbers you paid for. right?



JFWY thats cool. i'll figure it out at some point i'm sure. i just need to understand more how it all works. maybe i should find a school the navy could send me to, to learn this stuff. wouldn't that be cool.

[4.8t]

What's your commanded when idling at 13.9? By the way, the chances of you getting anywhere tuning adders in OL are slim. I mean, I suppose it's possible, but I don't really see how. With the trims going, the PWs are all over the place. Man that would drive me nuts!

i thought in OL the trims and stuff aren't working. i thought close loop is where the O2's and all start working and trims come into play. which it was you set the close loop temp setting in hpt to 285 when tuning ve and maf.

[my_bd]

well you said you had to scale the adders down to get the idle and decel under control so technically there not the numbers you paid for. right?

JFWY thats cool. i'll figure it out at some point i'm sure. i just need to understand more how it all works. maybe i should find a school the navy could send me to, to learn this stuff. wouldn't that be cool.

yep I scaled them down only because my 2.0L engine cannot process all that fuel at idle. (I am fudging my numbers grrrrr...)

Your gigantic engine would not likely need to scale down the adders at all.

[4.8t]

are you atleast getting a 14.7afr idle? i can't seem to do that. plus my maf and ve are WAY out since the new injectors. so what gives here? even driving around town i'm getting 1.7-3.2ms PW's thats crusing at 50mph. why does this shit have to be such a pain in the ass? cruising around i'm getting 15 stft thats at say, 2400 rpm and 60kpa but at the same time my wide band says i'm -6% off of my commanded afr. so why would the trims tell the computer to go rich? thats what i don't get. i know i need to tune ve and maf with out trims and all that going but i can make all the adjustments i want to make it leaner and it won't work. unless it goes to lopeing around and 16:+ afr. are adjusments in .025ms increments for the adders too much?

i would still like to know why my injectors won't even try to go below 1.7ms. i have the min pulse set to .106 and the default set to .046. i should be able to go even lower with both as long as the adders are good correct?

here is a question. if an injector fires at say 1.7ms and it has no adder or an adder of zero and then fires at say 1.2 but has an adder of .5ms and the offset value is the same on both. do they fire the same amount of fuel?

[EC_Tune]

Your minimum pw and default pw are probably limiting you. They set the floor for injector PW and everything adds to them.

[4.8t]

should i set them to zero or almost zero to see?

[EC_Tune]

No. Try them around .7 - .9 msec.

[4.8t]

i have them at .1 and .046 as it is. should i raise them to .7 and .9?

[EC_Tune]

Guess I need to look over your file in the other thread...

[03Sierraslt]

I am still pissing with mine but its down for the winter for more mods so I cant play with it at the moment to test some ideas.

[03Sierraslt]

The main problem I have with mine is rich decel, however I am also fighting a idle afr issue. I can get it to idle where ever I want it afr wise but when I put it in drive the afr will drop like .8 or so. And its vise versa, if I tune idle in Drive then it drops when I put it i Park.... My offset table is by no means perfect. A very little throttle all the way to WO is perfectly fine afr wise, it does what I want. Damn returnless fuel system....

[SJSchafer]

The main problem I have with mine is rich decel, however I am also fighting a idle afr issue. I can get it to idle where ever I want it afr wise but when I put it in drive the afr will drop like .8 or so. And its vise versa, if I tune idle in Drive then it drops when I put it i Park.... My offset table is by no means perfect. A very little throttle all the way to WO is perfectly fine afr wise, it does what I want. Damn returnless fuel system....

Get real offset numbers. Check your PWs and adjust your adders.

[03Sierraslt]

Get real offset numbers. Check your PWs and adjust your adders.

I would love to get real offset Numbers... However that seems to be the problem.