Anyone noticed this? or is it just my car?
I dont think i have EVER seen my car command more than 13 afr when i am in VE tuning mode... (dfco set to 6000+ and ect closed loop maxed at 255)
This is all we are supposed to do to force the car into closed loop so we can tune the VE tables right?
So why is it that in this state it always commands like 10-13 afr... no matter what...
and then as soon as i change coolant temp and dfco back poof there is my 14+ again...
why is this? it is costing me an arm and a leg in gas for my tuning drives!!!
and i am sure it skews my ve accuracy as well as i am always pouring the fuel in.
When you disable closed loop it runs off of the tables that you tune. Then when you turn closed loop back on, it takes the input from the o2 and corrects the afr to stoich.
I wish my car liked closed loop
(Tom) S/C Fire wrote:When you disable closed loop it runs off of the tables that you tune. Then when you turn closed loop back on, it takes the input from the o2 and corrects the afr to stoich.
no no no no.... i know that much.... i am talking about the commanded AFR... what the computer is asking the car to run at....
when you do VE tuning... you are comparing what the computer asks for against what your car gives it... and then you adjust for the amout of error you have....
I am not talking about my car running rich cuz i tuned in too much fuel... i am talking about the fact that the computer never once asks for 14.6 while in open loop.... it always wants like 10 or 12 or maybe 13... i am talking about the field commanded AFR...
as soon as i turn the system back to driving mode (closed loop, and dfco on) suddenly the car starts asking for 14.6 and such again... but for the life of me i cant figure out why it wont do stoich in open loop.
It's to be safe. The tune is based on what it commands vs. what it actually is. It doesn't matter what it's targeting, if your VE tune is spot on you can tell it to target 14.6 and that's what it will be. When you VE tune it targets rich just to be safe.
It doesn't skew anything...
2001 Olds Alero (LD9)
650 whp / 543 ft-lb
@turboalero
ok... welll it sure targets my wallet.... shhesh... i like to take nice long drives to tune things in... and man alive... i can easily eat a tank of gas in a day or 2 of tuning.
and the car runs like crap as rich as it runs.
i cant imagine nearly stalling and sputtering all the time makes for a good tune...
i dont think your fuel trims are active in open loop, it always trys to hit the commanded afr you specify. mine is at 12.5 and it gets pretty close to it under wot when i turn closed loop back on.
only problem im really having is idle, its a little rich then it goes back to 14.6 then a little lean then back to 14.6 and stays if it didnt die when it went lean. you having that problem at all ken?
yea, it does use quite a bit of gas..
12.33 @ 111.67 mph [Oct 2009]
Dyno'd on 08/02/09 - Mustang Dyno:
327.6 WHP 333.6 WTQ [10.1 AFR]
Command AFR dose not mean dick.
its what is in the program that matters.
Chris
'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08
why do all the HPT threads make me want to
lately??
open loop doesn't want stoich.. thats kind of the whole f-ing point of open loop.
Taetsch Z-24 wrote:Command AFR dose not mean dick.
its what is in the program that matters.
Chris
where do you think the "program" comes from? commaned AFR is everything.... and your tune is entirely about making the car "follow commands" if your car does EXACTLY as the computer tells it... then you are "tuned"
DaFlyinSkwir(LS61) /PJ/ OEM+ wrote:why do all the HPT threads make me want to lately??
open loop doesn't want stoich.. thats kind of the whole f-ing point of open loop.
Open loop under WOT does not want stoich. Nor does it on cold startup, and yes, under normal driving yes you want closed loop for all stoich conditions... but this is the tuning forum... and i made it pretty clear that i am in FORCED OPEN LOOP for the purposes of VE tuning... soooo when i am cruising around logging... there is ALOT of times where open loop SHOULD want stoich... but it doesnt... but the "safety" factor pointed out by Ion C2 makes alot of sence. I guess HPT does that automatically... many other tuning programs leave that up to you, but tell you to tune rich, just to be safe.
evilmonkitar wrote:i dont think your fuel trims are active in open loop, it always trys to hit the commanded afr you specify. mine is at 12.5 and it gets pretty close to it under wot when i turn closed loop back on.
only problem im really having is idle, its a little rich then it goes back to 14.6 then a little lean then back to 14.6 and stays if it didnt die when it went lean. you having that problem at all ken?
yea, it does use quite a bit of gas..
No trims are disabled in open loop.
and the computer picks the commanded afr in cruise... you set it for WOT. But the computer always wants to see you hit the CMD afr what ever it is at that time.... that is what VE tuning is about... to have your tune match the flow of the engine, so that when the computer says "give me 14.6" it gets 14.6... if it says "give me 11" you get 11.
Yeah i have that problem more than a little bit.... when i come to a stop the RPM and AFR's begin to fluctuate slightly at first... and grow worse and worse till she stalls or i step on the gas. If you look at my graph view... you can always spot the idle.. it looks like a sideways tornado. tiny lil wave that gets larger and larger tll it flatlines.
nothing has been quite right since i put my 750cc injectors in... i am going to go back and force them to the calculated constant and then re-tune the entire VE range from there. and now there are a few other variable that have changed as well.... so i am just going to start from scratch... what is a few days of my time and a full tank of gas to drive around in closed loop.
ken soggs wrote:Open loop under WOT does not want stoich. Nor does it on cold startup, and yes, under normal driving yes you want closed loop for all stoich conditions... but this is the tuning forum... and i made it pretty clear that i am in FORCED OPEN LOOP for the purposes of VE tuning... soooo when i am cruising around logging... there is ALOT of times where open loop SHOULD want stoich... but it doesnt... but the "safety" factor pointed out by Ion C2 makes alot of sence. I guess HPT does that automatically... many other tuning programs leave that up to you, but tell you to tune rich, just to be safe.
closed loop utilizes multiple sensors to calculate desired fuel for stoich. If one of the sensors fail, the VE map is what the ecu will revert to. Not just the O2 sensor.. ECT, IAT, and in some cases MAP is just as important. If anyone of those sensors decides to crap-ola, the ecu defaults to open loop as a safety precaution. Ion C2 nailed it.
As a test, start your car (normal running mode.. closed loop is fine) and check commanded AFR. then unplug your IAT and see what happens. Then the ECT.. etc. I'd be curious to see what the ecu does in response.. I may actually perform the test myself.
but I reiterate, the POINT of open loop is to run straight off the VE table that is TUNED from the OEM to run the car as close to targeted AFR (on a stock eco, this is 13:1.. also used for PE AFR) even though in the real world, it rarely gets there (falling short and running lean) but the VE tables are NOT to be adjusted for stoich.
and to further throw a monkey wrench into your stoich tuning ideas, where are our startup tables? warmup enrichments? where is 'stoich' defined in our programming? I don't see any number than can be manipulated to alter what the ecu considers "stoich". Thats completely counter-intuitive, these tables/maps whatever you want to call them ARE there we just can't see them/edit them.
ken soggs wrote:
Yeah i have that problem more than a little bit.... when i come to a stop the RPM and AFR's begin to fluctuate slightly at first... and grow worse and worse till she stalls or i step on the gas. If you look at my graph view... you can always spot the idle.. it looks like a sideways tornado. tiny lil wave that gets larger and larger tll it flatlines.
Have you altered your low rpm coast down table at all?
K. Vega..Mr. M62 L61 himself. wrote:ken soggs wrote:
Yeah i have that problem more than a little bit.... when i come to a stop the RPM and AFR's begin to fluctuate slightly at first... and grow worse and worse till she stalls or i step on the gas. If you look at my graph view... you can always spot the idle.. it looks like a sideways tornado. tiny lil wave that gets larger and larger tll it flatlines.
Have you altered your low rpm coast down table at all?
Nope... i have not done that.... looked at it a few times... but havent touched it... primarily because i dont really know what it does... and i dont like to monkey with things unless i know what they do.
So sorry to piss people off by asking more "why" and "how"... But would anyone care to explain what the coastdown table actually does. I can assume it is when you let off the gas and coast... but what do the numbers in the cells mean? when does this kick in? what do we look at to figure out how to adjust it?
Also... anyone want to give me some info on what the injector pulsewidth multiplier table does.... and how this is best adjusted.....
I seem to have my low rpm VE's dialed in pretty decently... but my idle is crap... it is kind of odd... the cells right on the idle spot are fine... like the 4 cells right where the target idle is... but ALL the cells around it are WAYYYYYY out of whack... i am talking like 50% AFR error... but only 1-2 in the 4 center cells. but the idle table itself is as smooth as can be (almost stock) So how can this be? seems the more i try to tune it, the worse it gets. I am hoping my answer lies in coastdown or pulsewidth.
DaFlyinSkwir(LS61) /PJ/ OEM+ wrote: these tables/maps whatever you want to call them ARE there we just can't see them/edit them.
Hah! Tell that to HPtuners.
http://www.hptuners.com/forum/showthread.php?t=20255
Even better they aren't planning and adding jack squat for our PCMs on the next release of the software.
___________________________________________________________________
Hahn Stage II - Mitsu TD06-20g |3" Turbo-back Exhaust | 61mm Bored TB |
HP Tuners | Innovate WB02 | Spec Stage 3 | Team Green LSD | TurboTech Upper | Full Addco Sways | Sportlines & Yellows |
x2 - there must be a commanded AFR multiplier (vs RPM, vs IAT and vs ECT) other than the PE multiplier. Plus other open loop commanded AFR tables.
hmm... ok... to further throw a wrench in things.... i was out driving around in tuning mode and sure enough... after a while i noticed it actually did command 14.6 a few places.
so there goes the theory about "automatically goes rich for safety"
so i am confused now... 80% of my tuning is at a cmd afr of 13.x sometimes it drops to 12's... of course PE is lower yet.. (but i spend most of my time getting the low rpm tables accurate) But yeah.... for the first time i did indeed see it command stoich for a while....
So here is me again... needing to know why.... I guess i just feel more comfortable working on things when i know how they work. Surgeons are not allowed to cut open a patient untill they have memorized the anatomy backwards and upside down... I just would feel alot better working on this stuff if i knew how it worked and why it does what when.
What would be perfect would be a ECM math flow chart.... just a graph showing what the computer actually does to get its results, what tables are used at what times... i know alot of it... but far from all. And i dont think there are too many people on here (besides maybe shifted) who fully understand everything that goes into the ECM calculations.
#1 multiply all of your coast down values by 3 and see what that does for your car.
they are currently all at 10 (i think.. hpt not in front of me)... so you want me to set them to 30 across the chart?
and forgive me for asking.. but can you or anyone else tell me what this does? I will try it of course. be thrilled if it helps.. but what does this change? and when should this be changed? and where did you get the 3x figure? should it match the ve offset? or somehow goes along with injector constant?
ken soggs wrote:hmm... ok... to further throw a wrench in things.... i was out driving around in tuning mode and sure enough... after a while i noticed it actually did command 14.6 a few places.
so there goes the theory about "automatically goes rich for safety"
so i am confused now... 80% of my tuning is at a cmd afr of 13.x sometimes it drops to 12's... of course PE is lower yet.. (but i spend most of my time getting the low rpm tables accurate) But yeah.... for the first time i did indeed see it command stoich for a while....
So here is me again... needing to know why.... I guess i just feel more comfortable working on things when i know how they work. Surgeons are not allowed to cut open a patient untill they have memorized the anatomy backwards and upside down... I just would feel alot better working on this stuff if i knew how it worked and why it does what when.
What would be perfect would be a ECM math flow chart.... just a graph showing what the computer actually does to get its results, what tables are used at what times... i know alot of it... but far from all. And i dont think there are too many people on here (besides maybe shifted) who fully understand everything that goes into the ECM calculations.
I think with all your problems you would be best off putting stock s/c reflash injectors back in, put your PCM back to stock s/c config. Go drive the car (out of boost) and see if it drives normal, check your logs. Make sure there are no other problems (i.e. sensor issues etc)
You very well could just be compounding problems which is going to make it impossible to figure things out.
Also you have had to modify those injectors by adding the resistors so do you really know if they are working the way they should?
___________________________________________________________________
Hahn Stage II - Mitsu TD06-20g |3" Turbo-back Exhaust | 61mm Bored TB |
HP Tuners | Innovate WB02 | Spec Stage 3 | Team Green LSD | TurboTech Upper | Full Addco Sways | Sportlines & Yellows |
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ken soggs wrote:they are currently all at 10 (i think.. hpt not in front of me)... so you want me to set them to 30 across the chart?
and forgive me for asking.. but can you or anyone else tell me what this does? I will try it of course. be thrilled if it helps.. but what does this change? and when should this be changed? and where did you get the 3x figure? should it match the ve offset? or somehow goes along with injector constant?
exactly they are all 10 they should be if your running the stock ld9 reflash. set it to 30 or 40 and see what afrs and how your car behaves once you enter coast down post result.
K. Vega..Mr. M62 L61 himself. wrote:ken soggs wrote:they are currently all at 10 (i think.. hpt not in front of me)... so you want me to set them to 30 across the chart?
and forgive me for asking.. but can you or anyone else tell me what this does? I will try it of course. be thrilled if it helps.. but what does this change? and when should this be changed? and where did you get the 3x figure? should it match the ve offset? or somehow goes along with injector constant?
exactly they are all 10 they should be if your running the stock ld9 reflash. set it to 30 or 40 and see what afrs and how your car behaves once you enter coast down post result.
On the SC Reflash, the Costdown will be the number of the multiplier....
P&P Tuning
420.5whp / 359.8wtq
ImPhat0260/Cavattack2000 wrote: On the SC Reflash, the Costdown will be the number of the multiplier....
By multiplier, I assume you mean the "VE Offset"?
So if you change your offset to 60 then your Coastdown should also be changed to 60 across the board?
since the Reflash comes with a offset of 10... the coastdown should also be 10...
right?
ken soggs wrote:ImPhat0260/Cavattack2000 wrote: On the SC Reflash, the Costdown will be the number of the multiplier....
By multiplier, I assume you mean the "VE Offset"?
So if you change your offset to 60 then your Coastdown should also be changed to 60 across the board?
since the Reflash comes with a offset of 10... the coastdown should also be 10...
right?
Correct... This is only true with the SC reflash though...
P&P Tuning
420.5whp / 359.8wtq
