Dialing in MAF tables anyone????
01-14-2005, 12:54 AM
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Originally Posted by WS6snake-eater
Looks like you have the table dialed in pretty damn good to me 
The reason that I wanted you to do this, is because it creates a visual picture of what I was saying earlier about how the method does not have you tuning for a specific AFR but rather setting up an accurate base air table, for the computer to reference for fueling needs....Damn that was a long run on sentence...
Hopefully now you see what I mean. However we still have to figure out what the problem is with your tune. We know now that it is something in the closed loop configs, because the car is achieving the commanded AFR while in open loop. Go ahead and drop me a copy of your bin file to ws6snake_eater@hotmail.com and I will have a look at your closed loop params. Do you have LT headers? How old are your o2's?
Matt
The reason that I wanted you to do this, is because it creates a visual picture of what I was saying earlier about how the method does not have you tuning for a specific AFR but rather setting up an accurate base air table, for the computer to reference for fueling needs....Damn that was a long run on sentence...
Hopefully now you see what I mean. However we still have to figure out what the problem is with your tune. We know now that it is something in the closed loop configs, because the car is achieving the commanded AFR while in open loop. Go ahead and drop me a copy of your bin file to ws6snake_eater@hotmail.com and I will have a look at your closed loop params. Do you have LT headers? How old are your o2's?
Matt
I was thinking about the VE function and how one of the variables is the IAT... If you re-arrange the function to solve for dynamic airflow as seen here:
https://ls1tech.com/forums/pcm-diagnostics-tuning/149741-ve-table-cracked.html
then you'd see that the IAT becomes the divisor... which means lower IATs mean higher dynamic airflow. So that should be the case since the weather dropped temps here in Austin, but what gets me is that if I have higher dynamic airflow that should push me lean am I right? My MAF table was built to line directly up to the dynamic airflow (and it does, this is what the thread was originally about) so in relation to the MAF, in non-SD mode (MAF operation and referencing), OL or CL, my dynamic airflow ought to register slighty higher than the MAF readings as IATs get colder... which if that were the case the motor would be in a lean condition and add fuel, not subtract.
But, as we can see, I tried to verify my VE table today in open loop SD mode (Eliminating the MAF's bias) and it did not respond well in certain areas to the commanded AFR... So even without misinformation from the MAF my VE table still appears to be off... As a matter of fact it completely mimiced (spelling?) the closed loop operation log shown above (the log results of my rebuilt MAF table that I entered links to above) where the LTFTs show a VE that is not in sync with the commanded AFR as well. So what the hell is screwing up my VE table (even back in open loop mode) when you can clearly see that I've verfied it's accuracy before at commanding 13.0???? Something else to note, I did reset fuel trims again before logging the OL SD mode today so I know for sure there's no set VCM trims affecting the fueling...
So in OL or CL as of yesterday and today, colder weather and all, my VE table is not aligned with commanded AFR... But 3 days ago it was behaving perfectly... This has me kinda pissed now...
I did everything right, verified that the configuration was correct, changed absolutely nothing, reactivated closed loop a few days later (which we just discussed will not effectively change the actual VE table, only reference it), and now it's as if my VE table decided to undo itself??? The only difference being is that it got a little colder up here... And the closed loop AFR commander is a single value defined in the fuel control settings in HPT so the multiplier is flat across the whole VE table, with PE mode being the only variant commanded AFR... Please come up with something good!!! 
oh yeh, 3 days ago my car had zero surging, practically non existent bucking problems, and driveability was almost close to stock... today, my car has been surging a bit, bucking has increased slightly and it's basically a depreciation in drieability, which goes hand in hand with the discrepancies in my VE table now... what a headache!
Something else i was thinking about is maybe I'm not in SD mode... I set the MAF fail Frequency to zero and changed all the Delta P0101 table values to zero to "force" SD mode, which seems to work since i did log like this while acquiring MAF data to rebuild the table and was still commanding 13.0 and achieving that targeted AFR shown via wideband... when i changed those two MAF settings to try to force SD mode the only code it set off was the P0103... But for some reason I remebering reading somewhere that it's either the 101 or 102 code that bumps into SD.... might this be something problematic??? I'm not sure it would matter anyway though since the MAF has no contribution to the calculation of dynamic airflow right??? The MAF only adds to the trimming effect if not in conjunction with dyanmic airflow right?
Here is my AFR Histogram for the BIN file I had loaded in right before my current one... The only difference b/w this BIN and the one I have loaded now is that I constructed a new MAF table (which is completely aligned to dynamic airflow and verified in the scanner) and should not throw off fueling...
Now here's the histogram after I updated the MAF curve and reactivated closed loop... the AFR registers 14.7 like it should, but check out the trimming... those trims show be very very close to zero...
And if you download these log and config files you will see that I did build a good MAF table... look at the chart display and you can barely discern the two lines b/w Mass Airflow and dynamic Airflow...
Originally Posted by txhorns281
OK guys, here's the final result! Download the MAFCalibration.cfg file so your scanner will be setup to observe the results! I layed my MAF table right over my dynamic airflow and I sure am impressed... Now my only question is this.... Why are my LTFTs still so negative around low rpm and idle??? I tuned out my table via Wideband, SD/Open Loop pretty dang close to 13.0 as WS6Snake-Eater's write up suggested... Then, I aligned my MAF table to my dyanmic airflow as you can see on the LOG file here...
*EDIT* apparently these files might not work on older versions of HPT... a buddy of mine just tried to view then and could not... I used v1.5
MAF Tune Config File for HP Tuners scanner (Right-click save as please!)
MAF Tune Log File (Right-click save as please!)
but check out the LTFTs in the histogram... I have a few ideas about what's going on here... but some seem inconsistent...
*EDIT* apparently these files might not work on older versions of HPT... a buddy of mine just tried to view then and could not... I used v1.5
MAF Tune Config File for HP Tuners scanner (Right-click save as please!)
MAF Tune Log File (Right-click save as please!)
but check out the LTFTs in the histogram... I have a few ideas about what's going on here... but some seem inconsistent...
Last edited by txhorns281; 01-14-2005 at 01:41 AM.
01-14-2005, 09:10 PM
#62
txhorns281 - This might help you with your new MAF/LTFTs -> http://www.hptuners.com/forum/YaBB.p...num=1078851555
FWIW.
FWIW.
01-14-2005, 09:24 PM
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tx if your ve table is dialed in it doesn’t matter what you command your afr to mimic it WILL happen
the stock open loop fa table commands 14.7 and your commanded 13.0 in your SD tune. Your ve table is dialed in because you AFR matches what your put in the open loop fa table no matter what the AFR. All you are doing with the ve table is telling the PCM how much air is entering the engine. It then figures out how much fuel is needed Air is air and unless you physically change something (intake, exhaust, tb, bigger maf) this should stay pretty consistent. You are telling the PCM that this amount of air is entering the car it then figure out how much fuel. AFR shouldn’t matter and if commanded 9:1 it would do it. The ve table is an air mass table you are hard coding the air the engine intakes the only thing that changes is the AFR but since you and the pcm knows how much air the engine needs and wants it can figure out the fuel and you can verify that via your WB. Another check is to log the commanded AFR pid this coupled with your WB should move together accordingly.
Just as Ws6snakeeaterr says your ve table is dialed in try not to over think this too much as it is simpler that you are making it
the stock open loop fa table commands 14.7 and your commanded 13.0 in your SD tune. Your ve table is dialed in because you AFR matches what your put in the open loop fa table no matter what the AFR. All you are doing with the ve table is telling the PCM how much air is entering the engine. It then figures out how much fuel is needed Air is air and unless you physically change something (intake, exhaust, tb, bigger maf) this should stay pretty consistent. You are telling the PCM that this amount of air is entering the car it then figure out how much fuel. AFR shouldn’t matter and if commanded 9:1 it would do it. The ve table is an air mass table you are hard coding the air the engine intakes the only thing that changes is the AFR but since you and the pcm knows how much air the engine needs and wants it can figure out the fuel and you can verify that via your WB. Another check is to log the commanded AFR pid this coupled with your WB should move together accordingly.
Just as Ws6snakeeaterr says your ve table is dialed in try not to over think this too much as it is simpler that you are making it
01-14-2005, 10:20 PM
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Originally Posted by HumpinSS
tx if your ve table is dialed in it doesn’t matter what you command your afr to mimic it WILL happen
the stock open loop fa table commands 14.7 and your commanded 13.0 in your SD tune. Your ve table is dialed in because you AFR matches what your put in the open loop fa table no matter what the AFR. All you are doing with the ve table is telling the PCM how much air is entering the engine. It then figures out how much fuel is needed Air is air and unless you physically change something (intake, exhaust, tb, bigger maf) this should stay pretty consistent. You are telling the PCM that this amount of air is entering the car it then figure out how much fuel. AFR shouldn’t matter and if commanded 9:1 it would do it. The ve table is an air mass table you are hard coding the air the engine intakes the only thing that changes is the AFR but since you and the pcm knows how much air the engine needs and wants it can figure out the fuel and you can verify that via your WB. Another check is to log the commanded AFR pid this coupled with your WB should move together accordingly.
Just as Ws6snakeeaterr says your ve table is dialed in try not to over think this too much as it is simpler that you are making it
the stock open loop fa table commands 14.7 and your commanded 13.0 in your SD tune. Your ve table is dialed in because you AFR matches what your put in the open loop fa table no matter what the AFR. All you are doing with the ve table is telling the PCM how much air is entering the engine. It then figures out how much fuel is needed Air is air and unless you physically change something (intake, exhaust, tb, bigger maf) this should stay pretty consistent. You are telling the PCM that this amount of air is entering the car it then figure out how much fuel. AFR shouldn’t matter and if commanded 9:1 it would do it. The ve table is an air mass table you are hard coding the air the engine intakes the only thing that changes is the AFR but since you and the pcm knows how much air the engine needs and wants it can figure out the fuel and you can verify that via your WB. Another check is to log the commanded AFR pid this coupled with your WB should move together accordingly.
Just as Ws6snakeeaterr says your ve table is dialed in try not to over think this too much as it is simpler that you are making it
01-14-2005, 10:27 PM
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right right, I see what you are saying, after logging a few runs I can see what you mean... But lemme ask this then... you've seen the I dialed in my VE and verified it's stability at 13.0... but when I command 14.7 out of it, in either closed loop or open loop F/A table, it for some reason runs rich around idle and low rpm/low MAP values... And this is also regardless of whether or not I'm running in SD mode... I've logged in closed loop SD, open loop SD, closed non SD, and open non SD and it still makes my table seem "off" at idle and low rpm/MAP... So WTF is going on here??? I mean thank you guys for your patience in trying to understand this thing, but like you said, if my VE table is good (and it is) when i command 14.7 i should get 14.7... which for the most part i do except the parts of the table I keep bringing up...
Here's one more verification today.... this was after i made some corrections to the the VE in response to the richness that occurs at idle and low rpm/MAP when commanding 14.7. It still is rich, but a little bit better, but as procedure suggests, I should not have had to change anything since my VE was doing just fine at commanded 13.0...
Open Loop, SD mode, commanding 14.628, PE commanding 12.5
I don't really care about the rest of the table, it seems fine... but just this part, i mean those should be alot closer to 14.628 than they are am I right???
Somethings got to be messin it up
I mean thank you guys for your patience in trying to understand this thing, but like you said, if my VE table is good (and it is) when i command 14.7 i should get 14.7... which for the most part i do except the parts of the table I keep bringing up...Here's one more verification today.... this was after i made some corrections to the the VE in response to the richness that occurs at idle and low rpm/MAP when commanding 14.7. It still is rich, but a little bit better, but as procedure suggests, I should not have had to change anything since my VE was doing just fine at commanded 13.0...
Open Loop, SD mode, commanding 14.628, PE commanding 12.5
I don't really care about the rest of the table, it seems fine... but just this part, i mean those should be alot closer to 14.628 than they are am I right???
Somethings got to be messin it up
Originally Posted by HumpinSS
tx if your ve table is dialed in it doesn’t matter what you command your afr to mimic it WILL happen
the stock open loop fa table commands 14.7 and your commanded 13.0 in your SD tune. Your ve table is dialed in because you AFR matches what your put in the open loop fa table no matter what the AFR. All you are doing with the ve table is telling the PCM how much air is entering the engine. It then figures out how much fuel is needed Air is air and unless you physically change something (intake, exhaust, tb, bigger maf) this should stay pretty consistent. You are telling the PCM that this amount of air is entering the car it then figure out how much fuel. AFR shouldn’t matter and if commanded 9:1 it would do it. The ve table is an air mass table you are hard coding the air the engine intakes the only thing that changes is the AFR but since you and the pcm knows how much air the engine needs and wants it can figure out the fuel and you can verify that via your WB. Another check is to log the commanded AFR pid this coupled with your WB should move together accordingly.
Just as Ws6snakeeaterr says your ve table is dialed in try not to over think this too much as it is simpler that you are making it
the stock open loop fa table commands 14.7 and your commanded 13.0 in your SD tune. Your ve table is dialed in because you AFR matches what your put in the open loop fa table no matter what the AFR. All you are doing with the ve table is telling the PCM how much air is entering the engine. It then figures out how much fuel is needed Air is air and unless you physically change something (intake, exhaust, tb, bigger maf) this should stay pretty consistent. You are telling the PCM that this amount of air is entering the car it then figure out how much fuel. AFR shouldn’t matter and if commanded 9:1 it would do it. The ve table is an air mass table you are hard coding the air the engine intakes the only thing that changes is the AFR but since you and the pcm knows how much air the engine needs and wants it can figure out the fuel and you can verify that via your WB. Another check is to log the commanded AFR pid this coupled with your WB should move together accordingly.
Just as Ws6snakeeaterr says your ve table is dialed in try not to over think this too much as it is simpler that you are making it
01-15-2005, 09:19 AM
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Originally Posted by txhorns281
right right, I see what you are saying, after logging a few runs I can see what you mean... But lemme ask this then... you've seen the I dialed in my VE and verified it's stability at 13.0... but when I command 14.7 out of it, in either closed loop or open loop F/A table, it for some reason runs rich around idle and low rpm/low MAP values... And this is also regardless of whether or not I'm running in SD mode... I've logged in closed loop SD, open loop SD, closed non SD, and open non SD and it still makes my table seem "off" at idle and low rpm/MAP... So WTF is going on here??? I mean thank you guys for your patience in trying to understand this thing, but like you said, if my VE table is good (and it is) when i command 14.7 i should get 14.7... which for the most part i do except the parts of the table I keep bringing up...
Here's one more verification today.... this was after i made some corrections to the the VE in response to the richness that occurs at idle and low rpm/MAP when commanding 14.7. It still is rich, but a little bit better, but as procedure suggests, I should not have had to change anything since my VE was doing just fine at commanded 13.0...
Open Loop, SD mode, commanding 14.628, PE commanding 12.5
I don't really care about the rest of the table, it seems fine... but just this part, i mean those should be alot closer to 14.628 than they are am I right???
Somethings got to be messin it up
I mean thank you guys for your patience in trying to understand this thing, but like you said, if my VE table is good (and it is) when i command 14.7 i should get 14.7... which for the most part i do except the parts of the table I keep bringing up...Here's one more verification today.... this was after i made some corrections to the the VE in response to the richness that occurs at idle and low rpm/MAP when commanding 14.7. It still is rich, but a little bit better, but as procedure suggests, I should not have had to change anything since my VE was doing just fine at commanded 13.0...
Open Loop, SD mode, commanding 14.628, PE commanding 12.5
I don't really care about the rest of the table, it seems fine... but just this part, i mean those should be alot closer to 14.628 than they are am I right???
Somethings got to be messin it up
No. I hadn't seen that on a wideband yet, but I had a feeling that was happening. I am pretty sure it has to do with unburnt fuel getting sucked into your exhaust because of your cam. It should throw off any O2 sensor you have back there, narrow or wide band. That is exactly the same reason I was testing my car in open loop with the AF ratio locked at about 12:1. In closed loop our cars are probably running lean because all that fuel is throwing off the computer. Computer controlled fueling was not exactly designed with that sort of variable involved.
One thing is for sure. Your DFCO is not working, or those cells at the top would be going the other direction and throwing you off too.
01-15-2005, 10:29 AM
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Originally Posted by Another_User
No "and then..."!
No. I hadn't seen that on a wideband yet, but I had a feeling that was happening. I am pretty sure it has to do with unburnt fuel getting sucked into your exhaust because of your cam. It should throw off any O2 sensor you have back there, narrow or wide band. That is exactly the same reason I was testing my car in open loop with the AF ratio locked at about 12:1. In closed loop our cars are probably running lean because all that fuel is throwing off the computer. Computer controlled fueling was not exactly designed with that sort of variable involved.
One thing is for sure. Your DFCO is not working, or those cells at the top would be going the other direction and throwing you off too.
No. I hadn't seen that on a wideband yet, but I had a feeling that was happening. I am pretty sure it has to do with unburnt fuel getting sucked into your exhaust because of your cam. It should throw off any O2 sensor you have back there, narrow or wide band. That is exactly the same reason I was testing my car in open loop with the AF ratio locked at about 12:1. In closed loop our cars are probably running lean because all that fuel is throwing off the computer. Computer controlled fueling was not exactly designed with that sort of variable involved.
One thing is for sure. Your DFCO is not working, or those cells at the top would be going the other direction and throwing you off too.
I mean if that's the way it is then that's the way it is... at least in open loop i won't have any "false" trimming to mess up my VE transitions... I noticed that when running in closed loop my driveability had deteriorated a bit, most likely due to the o2s being "lied" to... So there is no cure for this???So what does this factor do for fuel economy??? Kinda sucks that i'm burning off fuel that doesn't contribute to combustion...
But then again, it's kinda nice that i got 400 horses... As far as the DFCO I haven't changed any of the stock settings but like you said it seems like it either is malfunctioning or just not aggressively set... I've heard of improved fuel economy through playing with the DFCO, any tips???
01-15-2005, 10:51 AM
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Wow...I haven't been around here for the last couple of days, but it seems like you are starting to get this figured out. A couple of other things, post up a pick of your LTFT boundries and of your o2 swing points, perhaps we can work on getting some of your drivability back, and kill some of the stink.
01-15-2005, 07:53 PM
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*EDIT* This is TXHorns281 posting...
Now this is interesting... I'm sure my LTFT Boundaries aren't supposed to be like that.... I don't know much about the functionality of boundaries so if anyone can educate a **** some more! I see trends in these pictures but don't know what they mean.
BTW, the trims settled down a little bit more, but they still were richer than commanded when we've proven before that they should clearly be inline... That whole sucking gas into the exhaust thing though would mean that my wideband would see richness, but the motor would still be running just fine correct?
Someone verify these statements:
1. The o2s would also see this richness in closed loop and falsely correct the
VE
2. In open loop there would be no trimming, and my VE would be referenced and working well and probably producing commanded AFR. But that gas thing makes verifying AFR seem as if the VE is "rich"
3. I'm guessing the gas sucking problem wasn't present when in open loop, commanding 13.0. Could it be the case that the verfication of commanded 13.0 is also false because of the gas sucking?
To be continued....
Now this is interesting... I'm sure my LTFT Boundaries aren't supposed to be like that.... I don't know much about the functionality of boundaries so if anyone can educate a **** some more! I see trends in these pictures but don't know what they mean.
BTW, the trims settled down a little bit more, but they still were richer than commanded when we've proven before that they should clearly be inline... That whole sucking gas into the exhaust thing though would mean that my wideband would see richness, but the motor would still be running just fine correct?
Someone verify these statements:
1. The o2s would also see this richness in closed loop and falsely correct the
VE
2. In open loop there would be no trimming, and my VE would be referenced and working well and probably producing commanded AFR. But that gas thing makes verifying AFR seem as if the VE is "rich"
3. I'm guessing the gas sucking problem wasn't present when in open loop, commanding 13.0. Could it be the case that the verfication of commanded 13.0 is also false because of the gas sucking?
To be continued....
01-15-2005, 10:42 PM
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Originally Posted by WS6snake-eater
What is your commanded idle RPM?
The only other idle thing i changed was Base Running Airflow at operating temps is set at 10.00
Last edited by txhorns281; 01-16-2005 at 12:53 AM.
WERD.....
01-17-2005, 05:07 PM
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Man I totally forgot that you sent it. Yeah I just checked it and it is there. I have practice tonight, so I will try and give it a look see tomorrow. I'll also try to get a little something on the FT cells written up for ya! Judging by where you have your boundries set, it is very possible that it might be messing with you a little. I would also tighten up the o2 swing points, that will help with the smell a bit, and gas milage as well. I've give it a good look tomorrow after work.l
01-17-2005, 08:33 PM
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Originally Posted by WS6snake-eater
Man I totally forgot that you sent it. Yeah I just checked it and it is there. I have practice tonight, so I will try and give it a look see tomorrow. I'll also try to get a little something on the FT cells written up for ya! Judging by where you have your boundries set, it is very possible that it might be messing with you a little. I would also tighten up the o2 swing points, that will help with the smell a bit, and gas milage as well. I've give it a good look tomorrow after work.l
01-17-2005, 09:34 PM
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I have been looking at some of what the custom tuners have been doing (mostly the supercharged Magnusson one I was looking over. It looks like some sort of doctored hybrid of a couple different stock PCM tunes in a few places. Weird.
01-17-2005, 09:56 PM
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Originally Posted by Another_User
I have been looking at some of what the custom tuners have been doing (mostly the supercharged Magnusson one I was looking over. It looks like some sort of doctored hybrid of a couple different stock PCM tunes in a few places. Weird.
01-18-2005, 08:42 AM
#79
This thread has some interesting discussions, especially earlier, talking about getting your MAF to be correcty calibrated. I went with few suggestions I found in here, and I gathered a bunch of points of
MAF Hz vs MAF raw, MAF dynamic, and MAF SAE, then I got the formulas for all of them. the results are discussed in this hptuners board thread.
http://www.hptuners.com/forum/YaBB.p...num=1105401117
Also, JimMueller, I figured out how to do all the array formulas, LINEST, and solving for cooficients of high order polynomials with formulas, not trendlines on graphs. If you're still looking for these excel tricks, let me know, I'll send you my spreadsheet.
Let me know what you think of my results or methodology.
Marcin
MAF Hz vs MAF raw, MAF dynamic, and MAF SAE, then I got the formulas for all of them. the results are discussed in this hptuners board thread.
http://www.hptuners.com/forum/YaBB.p...num=1105401117
Also, JimMueller, I figured out how to do all the array formulas, LINEST, and solving for cooficients of high order polynomials with formulas, not trendlines on graphs. If you're still looking for these excel tricks, let me know, I'll send you my spreadsheet.
Let me know what you think of my results or methodology.
Marcin
01-18-2005, 01:59 PM
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Originally Posted by RedHardSupra
This thread has some interesting discussions, especially earlier, talking about getting your MAF to be correcty calibrated. I went with few suggestions I found in here, and I gathered a bunch of points of
MAF Hz vs MAF raw, MAF dynamic, and MAF SAE, then I got the formulas for all of them. the results are discussed in this hptuners board thread.
http://www.hptuners.com/forum/YaBB.p...num=1105401117
Also, JimMueller, I figured out how to do all the array formulas, LINEST, and solving for cooficients of high order polynomials with formulas, not trendlines on graphs. If you're still looking for these excel tricks, let me know, I'll send you my spreadsheet.
Let me know what you think of my results or methodology.
Marcin
MAF Hz vs MAF raw, MAF dynamic, and MAF SAE, then I got the formulas for all of them. the results are discussed in this hptuners board thread.
http://www.hptuners.com/forum/YaBB.p...num=1105401117
Also, JimMueller, I figured out how to do all the array formulas, LINEST, and solving for cooficients of high order polynomials with formulas, not trendlines on graphs. If you're still looking for these excel tricks, let me know, I'll send you my spreadsheet.
Let me know what you think of my results or methodology.
Marcin
In HPT, the MAF reports in g/sec so I just converted those dynamic AF averges (lb/min) using the unit calculator and then for all the missing MAF frequencies (most likely since I won't be doing a whole lot of in that frequency range) I scaled the airflow values according to what the trend seemed to show as far as variance from the old MAF calibration for higher frequencies.
It was pretty easy and didn't give me any problems, just took a bit of time... then i logged my Mass AF vs my Dynamic AF after adjusting to see if the two were in line, and I mean you could barely differentiate between the two chart lines.... The MAF was reporting EXACTLY what the engine was using so minus the stupid low end trimming and A/F inconsistency that is mentioned in the latter half of this thread, I got my MAF totally lined up with the motor... Can anyone tell me if they see a hole in what I did???
