At wits' end ( short trip )

2 Attachment(s)

Working on an LS swap ( junk yard 6.0L LQ4 with 317 heads ) with 4L80e ( unknown history ) with 0411 computer (OS 12212156). It starts well but goes lean (15.5-16.5 AFR ) as it warms up and stays that way when driving ( afraid to drive it too far ). We are running a MAF. I must be adjusting in the wrong table or something because adjustments to the "open loop VE" table don't seem to help? What am I doing wrong?
Any help is greatly appreciated.

Attached what I am working with if someone that knows what they are looking at could look it over...

Thank you in advance,
Some Fool

If you are running a maf, VE won't make much difference until it goes to blended mode, example acceleration. Steady state operation is controlled mainly by the MAF. To tune the ve, you need to fail the MAF tune the VE, then turn the MAF back on and tune the MAF

Quote:

Originally Posted by ralmo94

If you are running a maf, VE won't make much difference until it goes to blended mode, example acceleration. Steady state operation is controlled mainly by the MAF. To tune the ve, you need to fail the MAF tune the VE, then turn the MAF back on and tune the MAF

YES, ^^^^^^this.
The most common mistakes are the pcv lines, pay CLOSE attention to how GM did it and adjust accordingly. Do NOT try to tune around it, especially in the MAF tables. Leave them alone and fix what is causing them to be wrong. Also, it is very common to have a bad MAF sensor reading low. In neutral it should favor around ~6 grams at 600 rpm and ~25 qms 2500 rpm on stock 6l engine. Most stock 6l engines will pull ~230 gms at ~6000 rpm. If you are a lot lower suspect the MAF sensor. Don't buy anything but a real Delphi sensor. I don't even trust AcDelco anymore since most crap is from China.

A recent example was I diagnosed a failing MAF sensor so the guy went down the street to NAPA and bought a 'refurb" MAF and it was worse than the one he had. Sent him back for a Delphi and problem solved except for the needed tune, and btw, stay out of the MAF table unless you think you are smarter that GM that spent who knows how many thousands of man hours making that table correct. If you have a tube screwing with your MAF table, throw it away ;)

Quote:

Originally Posted by In-Tech

YES, ^^^^^^this.
The most common mistakes are the pcv lines, pay CLOSE attention to how GM did it and adjust accordingly. Do NOT try to tune around it, especially in the MAF tables. Leave them alone and fix what is causing them to be wrong. Also, it is very common to have a bad MAF sensor reading low. In neutral it should favor around ~6 grams at 600 rpm and ~25 qms 2500 rpm on stock 6l engine. Most stock 6l engines will pull ~230 gms at ~6000 rpm. If you are a lot lower suspect the MAF sensor. Don't buy anything but a real Delphi sensor. I don't even trust AcDelco anymore since most crap is from China.

A recent example was I diagnosed a failing MAF sensor so the guy went down the street to NAPA and bought a 'refurb" MAF and it was worse than the one he had. Sent him back for a Delphi and problem solved except for the needed tune, and btw, stay out of the MAF table unless you think you are smarter that GM that spent who knows how many thousands of man hours making that table correct. If you have a tube screwing with your MAF table, throw it away ;)

Unless the MAF is in a stock intake system on a bone stock engine with nearly no overlap it can be 20%+ off in calibration.

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Sorry Fast, wrong!!!! If it's a cartridge MAF in a weird tube, correct. The truck MAF (Delphi AF10043) doesn't care unless it is too close to the throttle body(common mistake too).

It was always my understanding that MAF calibration was done on a test bench without the stock intake tube connected, or air filter. With tight radiuses and bends and what not, these could play with the speed of the air moving across different parts of the MAF.
It was also my understanding that some elements of the tune were left close enough and not dialed in to save time and money as the O2 sensors were required for fine tuning fuel trims anyway. If the MAF is always correct, why do we get fuel trims on bone stock vehicles with no mods, and no defective issues. If a swap was done and the stock intake tube was not able to be utilized I could see the MAF curve being off a little bit. Also it was my understanding that MAF's don't like big cams from the reversion due to overlap,as this causes a pressure wave.
I don't know. But I would definitely make sure everything is connected correctly before attempting to tune MAF curve, but I would also compare closed loop fuel trims to wide band and see if they agree.

Obviously GM doesn't tune EVERY vehicle, everything within "tolerance". example, We took a bone stock Camaro off the showroom floor to CARB so we could baseline our testing. Guess what? ...it failed bone stock. Got another one from the dealer, it passed...then we could do our aftermarket stuff and re-test for certification.
You are correct on big cams and reversion double hitting the MAF, this is why distance can be massive criteria, tube size matters for transport delay when tube is larger than the MAF, tuning the MAF table doesn't FIX this but it seems some people get in there and think they are fixing something, you might fix something in one instance and totally fubar it in another instance. Air temp is critical as well as barometer. Also why GM has an air temp sensor in the MAF and even have some MAP sensors with built in air temp.

Just food for thought :)

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First off, thank all of you all so much.

Ralmo94 I appreciate the clarification as I was unaware of how it works... Obvious new-b question..How do I "fail the MAF"? It is a swap and has the stock cam to the best of my knowledge.

In-Tech I am attaching a few pictures of how I ran the pcv lines and would appreciate guidance if anything looks like it was not routed correctly. The log indicates that the MAF is at 7.23g/s for 620 rpm ( close enough?) but didn't check any other speeds ( I am at about 5K ft above sea level if that matters) but both LTFT is 7.81?

Fast355 I am also including a picture of how I ran the intake tube to get a better idea of what I am working with.

Quote:

Originally Posted by Some Fool

First off, thank all of you all so much.

Ralmo94 I appreciate the clarification as I was unaware of how it works... Obvious new-b question..How do I "fail the MAF"?

You edit the dtc code for MAF sensor range. There are two codes either one will work. Basically there is a high and a low frequency. When too high or too low the MAF is determined faulty and it will revert to speed density and use the ve table. You need to change the code for 1st fault sets the ses light, and change the frequency to number that will automatically fail the MAF for example set the high range at like 2hrz. As soon as it reads over 2hrz it should trip the code and go to speed density, you can now tune your VE table

Obviously if you need to fix something with your pcv or something you want to do that first, as ve table is sensitive to any air flow changes.

Quote:

Originally Posted by In-Tech

Sorry Fast, wrong!!!! If it's a cartridge MAF in a weird tube, correct. The truck MAF (Delphi AF10043) doesn't care unless it is too close to the throttle body(common mistake too).

I am NOT wrong! I have personally witnessed that style MAF as well as the earlier LT1/Vortec/LS1 MAFs do the same thing. The one in particular, I swapped the stock intake tube and box back on to and proved the MAFs (tried 2 different ones) were just fine. I then stuck an 04 LS1 Vette MAF curve in it and it worked with only slight adjustments needed. 5.3L with a 10" long straight 3.75" coupler off the throttle body into a cone filter on a vehicle with very limited engine compartment space. GM uses that same MAF with numerous different airflow tables.

If what you said is correct, this would not happen. The only thing wrong here even was a missing air cleaner element. Fuel trims went +20% the moment the stock air box was mistakingly installed without a filter. Fuel trims were a little off with the open sensor end as well(probably from the mechanical fan blowing air across the sensor) Filter in place and they were sitting near perfect.
https://youtu.be/m-qJ58scPJE

My 4" cartidge MAF has a slightly modified GM Performance Crate 525 HP LS3 MAF curve but I need to add a flow straightner to it.

Update: I have pretty much soaked this thing in carb cleaner and have yet to find a leak, so right or wrong, I am moving forward with attempting to tune her. I have watched a few videos but everything seems to be centered around HPTune.. Is there a "how to" for gen 3 tuning?

Latest: Managed to fail the VE and get it running fairly well on “MAF only”, but still must be missing something because the short and long fuel trims still pull fuel out..? What am I missing here?

Quote:

Originally Posted by Some Fool

Latest: Managed to fail the VE and get it running fairly well on “MAF only”, but still must be missing something because the short and long fuel trims still pull fuel out..? What am I missing here?

You failed the VE and are running MAF only? If so, what did you change to do it?

Or did you mean to say you failed the MAF, so it will use the VE only?

Obviously I am lost in trying to do this. I tried to follow Goat Rope Garage vid. "GM Gen 3 MAF tuning Intro, The basics For Mass Air Flow", but he is using HP tune and I am using TunerPro RT so some stuff did not match exactly. As I understand it, this sets it up for "MAF only".
Right or wrong, this is what I did....
Threshold for Airflow calculation to 200
PE MAP Threshold to 0
Deselected Long Term Fuel Trim Correction
Closed Loop Temp Enable to 283
Added %15 to PE Modifier Based on RPM
Deselected Catalytic Converter Protection Enable ( I do not have Cats )
DFCO Enable Temp. set to 280
DFCO RPM all set to 12000
Deselect Use o2 with open Loop Commanded Fuel Table

AFRs looked ok ( around 13 to 15 ), but not steady and could not keep up with quick throttle changes..

It's a lot easier to dial the VE in, then turn MAF back on any further corrections apply to MAF if you dialed VE in real close.
You can also just drive so as to try and keep the engine in near steady state condition for MAF.
Disabling Decel, isn't a bad idea if you can't filter your loggs. If you can, you can just filter for throttle position above 1.

I will turn everything back on and try to run it.
I do have a wideband (AEM 30-0300 ), but have not been able to get it to log through TunerPro ( Blue pin 68 high and 28 low ).
What I cant understand is that the more fuel I give it, the more (STFT and LTFT ) it just takes out? For all practical purposes this ( except for home made intake tube and headers) is a "stock swap".. why am I so far off?

To log WBo2, you should connect the 0-5vlt analog signal to blue pin 55. This is egr position sensor .
You need to have commanded egr to 0, disable egr codes, and zero out egr fuel reduction and egr spark tables.
If you are keeping fuel trims on, all you can do is aim for 0 trim. If you go open loop, you can tune to 14.7 on your gauge, then turn cl back on and tune O2 swing points to match almost no trim.
If you add 10%, and the fuel trims take out 10%, then you add another 10%, fuel trims will now want to take out 20%, the further you get from true, the longer it takes for it to learn what's right.

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I adjusted your open loop fuel table to be commanding stoich, it was commanding a richer fuel mixture the way it was. I also set your stoich afr to 14.08 to reflect 10% ethanol in pump gas.

There are 2 files attached, one is set up for MAF only, the VE table will be ignored, the second file is SD only, so it will fail and ignore the MAF and run purely on the VE table. Feel free to give these a try and see if you can control your fueling a little easier.

EXCELLENT! That is the kind of help that I am looking for and appreciate this very much. I will try to wire the wide band next weekend as described but we threw in the "SD only" bin and made a few adjustments to the VE table just based on watching the displays and have made more progress today than any other day this year. Thank you so much.

I decided to prove a point with the whole intake tract altering the MAF calibration. This has a LS3 cartridge MAF in a 100mm tube with a Saxon PC 6:1 flow straightner in it. My van reacted the same way the stock van with the GM LT1/Vortec 3.5" MAF in the prior video did with a missing air filter. My MAF calibration started as a GM LS3 525 hp calibration and only needed slight changes to run correctly. From memory had to add about 12% down at 1500hz and remove 4% over 7,000 hz but otherwise it was extremely close. Remove the filter and it nearly stalls.

Excuse the mess outside, just pulled down an old above ground pool and working on a kitchen remodel and I have not had the time to load up a trailer to take to the dump yet. I have seen LS trucks do the same thing with cheap Spectre or Ebay warm air intakes that have a cone filter on the end even with the stock 85mm MAFs. Change the intake tract and you will be tuning the MAF transfer calibration.

https://youtu.be/OtgLUNThifc

Quote:

Originally Posted by Fast355

Change the intake tract and you will be tuning the MAF transfer calibration.

thank you for confirming what I always believed.
True or not I also believed that exhaust modification also alters it, air in air out.
Although maybe not enough to worry about?

Quote:

Originally Posted by ralmo94

thank you for confirming what I always believed.
True or not I also believed that exhaust modification also alters it, air in air out.
Although maybe not enough to worry about?

Headers definately throw the calibration off. If you took a stock engine and put headers on it, the PCM will read at a higher dymanic airflow and put it in an area of the timing map that GM tuned with very little advance.

Fast, I know you're a smart guy, obviously you came to realize this is smart http://www.saxonpc.com/100mm-cells-for-100.html
I end up using multiple honeycombs in intake tracts to calm the tumbling that can occur. When you alter a known good transfer function you will find it isn't accurate at different temps, barometric pressures, altitudes, humidity, etc.

Big camshafts and bad exhaust sometimes require the distance to the MAF to be changed to further away and if packaging doesn't allow this, time to switch to speed density. Sometimes a switch to e78 or e92 computers that allow dual MAF's is an option too.

Quote:

Originally Posted by In-Tech

Fast, I know you're a smart guy, obviously you came to realize this is smart http://www.saxonpc.com/100mm-cells-for-100.html
I end up using multiple honeycombs in intake tracts to calm the tumbling that can occur. When you alter a known good transfer function you will find it isn't accurate at different temps, barometric pressures, altitudes, humidity, etc.

Big camshafts and bad exhaust sometimes require the distance to the MAF to be changed to further away and if packaging doesn't allow this, time to switch to speed density. Sometimes a switch to e78 or e92 computers that allow dual MAF's is an option too.

I have not run across issues altering MAF transfer functions in nearly 20 years of tuning. Not saying it cannot happen, but it is not something I have seen in many different platforms. I mainly tune GM and Nissan.

I would not go to speed density, it is near pointless and not nearly as accurate. A recalibrated MAF transfer is far more accurate then the best speed density. I had two Dodges that never could achieve accurate fueling, atleast not like a GM or Nissan.

I also converted my TBI to an 85mm MAF years ago.

Quote:

Originally Posted by ralmo94

To log WBo2, you should connect the 0-5vlt analog signal to blue pin 55. This is egr position sensor .
You need to have commanded egr to 0, disable egr codes, and zero out egr fuel reduction and egr spark tables.
If you are keeping fuel trims on, all you can do is aim for 0 trim. If you go open loop, you can tune to 14.7 on your gauge, then turn cl back on and tune O2 swing points to match almost no trim.
If you add 10%, and the fuel trims take out 10%, then you add another 10%, fuel trims will now want to take out 20%, the further you get from true, the longer it takes for it to learn what's right.

Ralmo94
I am in the process of getting this all hooked up and adjusting the settings ( after work and should make more progress this weekend ), but the definitions file (.adx ) that I have does not have the egr listed. Would you or someone in this forum happen to have the one I need please?
Thank you in advance.

Quote:

Originally Posted by Some Fool

Ralmo94
I am in the process of getting this all hooked up and adjusting the settings ( after work and should make more progress this weekend ), but the definitions file (.adx ) that I have does not have the egr listed. Would you or someone in this forum happen to have the one I need please?
Thank you in advance.

I don't have any oBd2 ADX's, I primarily use HP tuners since I invested in there interface long ago. I wasn't aware there were any specific OS ADX's available?
What interface are you using, could you use a different loging program with it? Perhaps the torque app?

I am trying to get it to work with Tunerpro RT so that I can correlate the AFR with the proper square in the VE table with data tracing ( so far I am recording the screen and wide band with my phone.. effective, but not very precise and quite convoluted ). The adx file I was given was setup to use a post-cat-o2 but I have been unable to get it to work yet.

Quote:

Originally Posted by Fast355

I have not run across issues altering MAF transfer functions in nearly 20 years of tuning. Not saying it cannot happen, but it is not something I have seen in many different platforms. I mainly tune GM and Nissan.

I would not go to speed density, it is near pointless and not nearly as accurate. A recalibrated MAF transfer is far more accurate then the best speed density. I had two Dodges that never could achieve accurate fueling, atleast not like a GM or Nissan.

I also converted my TBI to an 85mm MAF years ago.

Hiya Fast, thanks for the reply. I think we are both on the same page and you obviously know how tricky MAF calibration can be. I am with you on a MAF calibration done correctly is much better than speed density. Of course if we can provide good blending for both, it does offer some redundant qualities if one fails. I mainly do GM, like you, and on the occasions I have to do a Ford(MAF only garbage) or a Dodge(SD even worse garbage) it's amazing how bad these things are and can still get thru CARB testing when stock or with somebody's(Rousch, SCT, many many others).

I grew up on SD tuning(early 90's), so, it doesn't bother me but MAF is king IMO.

I get a lot of tunes to do that someone else has completely screwed up the driveability. Many have spent a Lot of money and the MAF tune makes all the power, and can't drive at all at part throttle on different days, because they got into the maf tables figuring a percentage here a percentage there works fine. Plenty of times I just look at the MAF table(even on Fords) and just put it back to stock(if it has the range) and start over from stock. Fix the tube, or, stock MAF and go, Yuck.

Anyway, good to have a talk :)

Quote:

Originally Posted by In-Tech

Hiya Fast, thanks for the reply. I think we are both on the same page and you obviously know how tricky MAF calibration can be. I am with you on a MAF calibration done correctly is much better than speed density. Of course if we can provide good blending for both, it does offer some redundant qualities if one fails. I mainly do GM, like you, and on the occasions I have to do a Ford(MAF only garbage) or a Dodge(SD even worse garbage) it's amazing how bad these things are and can still get thru CARB testing when stock or with somebody's(Rousch, SCT, many many others).

I grew up on SD tuning(early 90's), so, it doesn't bother me but MAF is king IMO.

I get a lot of tunes to do that someone else has completely screwed up the driveability. Many have spent a Lot of money and the MAF tune makes all the power, and can't drive at all at part throttle on different days, because they got into the maf tables figuring a percentage here a percentage there works fine. Plenty of times I just look at the MAF table(even on Fords) and just put it back to stock(if it has the range) and start over from stock. Fix the tube, or, stock MAF and go, Yuck.

Anyway, good to have a talk :)

It is always good to discuss things with you Carl. I too started with speed density TBI/TPI and GM CCC Q-Jet.

I too have fixed vehicles for the same reason. I actually just fixed a bone stock 5.3L to LQ9 swap. Ran poorly on startup, idled like a WW2 tank, etc. Guy had paid $700 for a dyno tune and it only ran well at WOT. The shop did not even have the correct injector data in the tune. Not a huge deal at WOT but at part-throttle fueling was everywhere. I put a stock MAF cal back into it too because it had a stock airbox, stock intake tube and stock maf.

Hiya Fast, it's funny we were just talking about this.

I get a cam change guy who just came from the dyno shop a few days before. It hauls ass but can't drive it across town. I suck the file out and told him I will be in touch in a few days if I can help.

Holy fockin crapola.

Code:

Power Enrich Fuel Equiv. Ratio Vs. RPM RPM Eq. Ratio 0 1.260 250 1.260 500 1.260 750 1.260 1000 1.295 1250 1.315 1500 1.296 1750 1.276 2000 1.260 2250 1.310 2500 1.310 2750 1.310 3000 1.310 3250 1.451 3500 1.451 3750 1.486 4000 1.486 4250 1.486 4500 1.486 4750 1.510 5000 1.510 5250 1.510 5500 1.510 5750 1.510 6000 1.510 6250 1.510 6500 1.510 6750 1.510 7000 1.510 7250 1.510 7500 1.510 7750 1.510 8000 1.510 MAF Sensor Air Flow Vs. Output Frequency - Low Hz gm/sec 0 0.000 150 0.776 300 1.063 450 1.349 600 1.636 750 1.922 900 2.208 1050 2.571 1200 3.008 1350 3.522 1500 4.111 1650 4.776 1800 5.596 1950 6.524 2100 7.601 2250 8.694 2400 10.154 2550 11.604 2700 13.217 2850 15.005 3000 16.826 3150 18.971 3300 21.631 3450 24.375 3600 27.005 3750 30.191 3900 33.179 4050 36.450 4200 39.681 4350 44.158 4500 47.974 4650 52.450 4800 56.100 4950 62.110 5100 66.817 5250 72.034 5400 77.879 5550 84.013 5700 90.434 5850 97.143 6000 104.187 6150 111.576 6300 119.283 6450 127.308 6600 135.652 6750 144.468 6900 153.846 7050 163.656 7200 173.896 7350 184.567 7500 195.668 MAF Sensor Air Flow Vs. Output Frequency - High Hz gm/sec 7650 207.188 7800 219.126 7950 231.488 8100 244.275 8250 257.487 8400 271.480 8550 286.121 8700 301.342 8850 317.143 9000 333.523 9150 350.483 9300 368.023 9450 385.563 9600 403.103 9750 420.643 9900 438.184 10050 455.724 10200 473.264 10350 490.804 10500 508.344 10650 525.884 10800 543.424 10950 560.964 11100 578.504 11250 596.044 11400 613.584 11550 631.124 11700 648.664 11850 666.204 12000 683.744 12150 701.284 12300 718.824 12450 736.364 12600 753.904 12750 771.444 12900 788.984 13050 806.525 13200 824.065 13350 841.605 13500 859.145 13650 876.685 13800 894.225 13950 911.765 14100 929.305 14250 946.845 14400 964.385 14550 981.925 14700 999.465 14850 1017.005 15000 1034.545

OMFG, he had been into the MAF table like he was a Ford guy, the he PE corrected wide open throttle to "fix" his fack. Besides all his other f'ups, I threw the file away and started from stock so I could fix it.

Example of a couple things :)

Code:

Fixed Power Enrich Fuel Equiv. Ratio Vs. RPM RPM Eq. Ratio 0 1.180 250 1.180 500 1.180 750 1.180 1000 1.180 1250 1.180 1500 1.180 1750 1.180 2000 1.180 2250 1.180 2500 1.180 2750 1.180 3000 1.180 3250 1.180 3500 1.180 3750 1.180 4000 1.180 4250 1.180 4500 1.180 4750 1.180 5000 1.180 5250 1.180 5500 1.180 5750 1.180 6000 1.180 6250 1.180 6500 1.180 6750 1.180 7000 1.180 7250 1.180 7500 1.180 7750 1.180 8000 1.180 MAF Sensor Air Flow Vs. Output Frequency - Low Hz gm/sec 0 0.133 150 0.133 300 0.133 450 0.133 600 0.133 750 0.133 900 1.035 1050 1.778 1200 2.412 1350 2.989 1500 3.561 1650 4.179 1800 4.892 1950 5.722 2100 6.682 2250 7.782 2400 10.186 2550 12.590 2700 14.995 2850 17.183 3000 18.833 3150 19.616 3300 23.508 3450 26.507 3600 29.718 3750 32.162 3900 37.158 4050 40.582 4200 44.594 4350 48.470 4500 53.165 4650 57.727 4800 62.643 4950 67.510 5100 73.626 5250 80.031 5400 86.745 5550 93.794 5700 101.202 5850 108.997 6000 117.208 6150 125.865 6300 134.996 6450 144.631 6600 154.789 6750 165.475 6900 176.684 7050 188.418 7200 200.674 7350 213.451 7500 229.018 MAF Sensor Air Flow Vs. Output Frequency - High Hz gm/sec 7650 242.977 7800 257.488 7950 269.910 8100 282.754 8250 299.051 8400 312.863 8550 330.133 8700 344.324 8850 358.672 9000 377.055 9150 396.285 9300 416.082 9450 435.918 9600 455.266 9750 473.594 9900 490.367 10050 505.066 10200 538.938 10350 563.039 10500 587.859 10650 613.414 10800 639.719 10950 666.773 11100 694.594 11250 723.195 11400 752.578 11550 782.766 11700 813.766 11850 845.578 12000 878.227 12150 911.711 12300 946.055 12450 981.266 12600 1017.344 12750 1054.313 12900 1092.172 13050 1130.953 13200 1170.641 13350 1211.266 13500 1252.828 13650 1295.328 13800 1338.813 13950 1383.266 14100 1428.688 14250 1475.109 14400 1522.547 14550 1571.000 14700 1620.484 14850 1671.000 15000 1722.563

Quote:

Originally Posted by In-Tech

Hiya Fast, it's funny we were just talking about this.

I get a cam change guy who just came from the dyno shop a few days before. It hauls ass but can't drive it across town. I suck the file out and told him I will be in touch in a few days if I can help.

Holy fockin crapola.

Code:

Power Enrich Fuel Equiv. Ratio Vs. RPM RPM Eq. Ratio 0 1.260 250 1.260 500 1.260 750 1.260 1000 1.295 1250 1.315 1500 1.296 1750 1.276 2000 1.260 2250 1.310 2500 1.310 2750 1.310 3000 1.310 3250 1.451 3500 1.451 3750 1.486 4000 1.486 4250 1.486 4500 1.486 4750 1.510 5000 1.510 5250 1.510 5500 1.510 5750 1.510 6000 1.510 6250 1.510 6500 1.510 6750 1.510 7000 1.510 7250 1.510 7500 1.510 7750 1.510 8000 1.510 MAF Sensor Air Flow Vs. Output Frequency - Low Hz gm/sec 0 0.000 150 0.776 300 1.063 450 1.349 600 1.636 750 1.922 900 2.208 1050 2.571 1200 3.008 1350 3.522 1500 4.111 1650 4.776 1800 5.596 1950 6.524 2100 7.601 2250 8.694 2400 10.154 2550 11.604 2700 13.217 2850 15.005 3000 16.826 3150 18.971 3300 21.631 3450 24.375 3600 27.005 3750 30.191 3900 33.179 4050 36.450 4200 39.681 4350 44.158 4500 47.974 4650 52.450 4800 56.100 4950 62.110 5100 66.817 5250 72.034 5400 77.879 5550 84.013 5700 90.434 5850 97.143 6000 104.187 6150 111.576 6300 119.283 6450 127.308 6600 135.652 6750 144.468 6900 153.846 7050 163.656 7200 173.896 7350 184.567 7500 195.668 MAF Sensor Air Flow Vs. Output Frequency - High Hz gm/sec 7650 207.188 7800 219.126 7950 231.488 8100 244.275 8250 257.487 8400 271.480 8550 286.121 8700 301.342 8850 317.143 9000 333.523 9150 350.483 9300 368.023 9450 385.563 9600 403.103 9750 420.643 9900 438.184 10050 455.724 10200 473.264 10350 490.804 10500 508.344 10650 525.884 10800 543.424 10950 560.964 11100 578.504 11250 596.044 11400 613.584 11550 631.124 11700 648.664 11850 666.204 12000 683.744 12150 701.284 12300 718.824 12450 736.364 12600 753.904 12750 771.444 12900 788.984 13050 806.525 13200 824.065 13350 841.605 13500 859.145 13650 876.685 13800 894.225 13950 911.765 14100 929.305 14250 946.845 14400 964.385 14550 981.925 14700 999.465 14850 1017.005 15000 1034.545

OMFG, he had been into the MAF table like he was a Ford guy, the he PE corrected wide open throttle to "fix" his fack. Besides all his other f'ups, I threw the file away and started from stock so I could fix it.

Example of a couple things :)

Code:

Fixed Power Enrich Fuel Equiv. Ratio Vs. RPM RPM Eq. Ratio 0 1.180 250 1.180 500 1.180 750 1.180 1000 1.180 1250 1.180 1500 1.180 1750 1.180 2000 1.180 2250 1.180 2500 1.180 2750 1.180 3000 1.180 3250 1.180 3500 1.180 3750 1.180 4000 1.180 4250 1.180 4500 1.180 4750 1.180 5000 1.180 5250 1.180 5500 1.180 5750 1.180 6000 1.180 6250 1.180 6500 1.180 6750 1.180 7000 1.180 7250 1.180 7500 1.180 7750 1.180 8000 1.180 MAF Sensor Air Flow Vs. Output Frequency - Low Hz gm/sec 0 0.133 150 0.133 300 0.133 450 0.133 600 0.133 750 0.133 900 1.035 1050 1.778 1200 2.412 1350 2.989 1500 3.561 1650 4.179 1800 4.892 1950 5.722 2100 6.682 2250 7.782 2400 10.186 2550 12.590 2700 14.995 2850 17.183 3000 18.833 3150 19.616 3300 23.508 3450 26.507 3600 29.718 3750 32.162 3900 37.158 4050 40.582 4200 44.594 4350 48.470 4500 53.165 4650 57.727 4800 62.643 4950 67.510 5100 73.626 5250 80.031 5400 86.745 5550 93.794 5700 101.202 5850 108.997 6000 117.208 6150 125.865 6300 134.996 6450 144.631 6600 154.789 6750 165.475 6900 176.684 7050 188.418 7200 200.674 7350 213.451 7500 229.018 MAF Sensor Air Flow Vs. Output Frequency - High Hz gm/sec 7650 242.977 7800 257.488 7950 269.910 8100 282.754 8250 299.051 8400 312.863 8550 330.133 8700 344.324 8850 358.672 9000 377.055 9150 396.285 9300 416.082 9450 435.918 9600 455.266 9750 473.594 9900 490.367 10050 505.066 10200 538.938 10350 563.039 10500 587.859 10650 613.414 10800 639.719 10950 666.773 11100 694.594 11250 723.195 11400 752.578 11550 782.766 11700 813.766 11850 845.578 12000 878.227 12150 911.711 12300 946.055 12450 981.266 12600 1017.344 12750 1054.313 12900 1092.172 13050 1130.953 13200 1170.641 13350 1211.266 13500 1252.828 13650 1295.328 13800 1338.813 13950 1383.266 14100 1428.688 14250 1475.109 14400 1522.547 14550 1571.000 14700 1620.484 14850 1671.000 15000 1722.563

Just fixed a stock LQ9 myself that a local dyno shop screwed up badly. Made good power at WOT, but idled and drove terribly. 4L60E was shifting terribly because they axed all torque management out of it. They claimed it had bad knock sensors. Still had the 5.3L knock sensor calibration that they just Zerod out its ability to retard timing.

Quote:

Originally Posted by Fast355

I am NOT wrong! I have personally witnessed that style MAF as well as the earlier LT1/Vortec/LS1 MAFs do the same thing. The one in particular, I swapped the stock intake tube and box back on to and proved the MAFs (tried 2 different ones) were just fine. I then stuck an 04 LS1 Vette MAF curve in it and it worked with only slight adjustments needed. 5.3L with a 10" long straight 3.75" coupler off the throttle body into a cone filter on a vehicle with very limited engine compartment space. GM uses that same MAF with numerous different airflow tables.

If what you said is correct, this would not happen. The only thing wrong here even was a missing air cleaner element. Fuel trims went +20% the moment the stock air box was mistakingly installed without a filter. Fuel trims were a little off with the open sensor end as well(probably from the mechanical fan blowing air across the sensor) Filter in place and they were sitting near perfect.
https://youtu.be/m-qJ58scPJE

My 4" cartidge MAF has a slightly modified GM Performance Crate 525 HP LS3 MAF curve but I need to add a flow straightner to it.

if nots not a lot of work, would you mind sharing a file with this MAF curve?

i plan to run the cartridge MAF (LS7?) in a 4" tube and would be tickled to have a base curve to start tuning with. Thanks.

1 Attachment(s)

Quote:

Originally Posted by bobcratchet555

if nots not a lot of work, would you mind sharing a file with this MAF curve?

i plan to run the cartridge MAF (LS7?) in a 4" tube and would be tickled to have a base curve to start tuning with. Thanks.

Just threw it into an Open Office file. Should be easier to open generically than an BIN, HPT or Tunercats file for some.

Quote:

Originally Posted by Fast355

Just threw it into an Open Office file. Should be easier to open generically than an BIN, HPT or Tunercats file for some.

much appreciated, thank you

Quote:

Originally Posted by ralmo94

To log WBo2, you should connect the 0-5vlt analog signal to blue pin 55. This is egr position sensor .
You need to have commanded egr to 0, disable egr codes, and zero out egr fuel reduction and egr spark tables.
If you are keeping fuel trims on, all you can do is aim for 0 trim. If you go open loop, you can tune to 14.7 on your gauge, then turn cl back on and tune O2 swing points to match almost no trim.
If you add 10%, and the fuel trims take out 10%, then you add another 10%, fuel trims will now want to take out 20%, the further you get from true, the longer it takes for it to learn what's right.

Does anyone have an .adx file for OS 12212156 that they are willing to share to make this possible? Please
Thank you in advance.
Some Fool

Update: I was able to get the VE and MAF bins dialed in quite close however as soon as I turn everything back on and the truck starts using the O2 information it goes to 15.8-16.1:1 AFR.. The trims are about %5 ( both banks ) and the O2s are swinging between 0.3V and 1.0V.. All of the spark plugs are showing lean ( to my untrained eye ) and all of the injectors are firing ( all made a significant change when unplugged ). I have drenched this thing several times trying to find a vacuum leak ( I would think that it would not behave in the VE only tune if it were leaking? ). Adjusting the switching points in both directions had no effect. What am I missing? Two bad 02s ( seemed fine in a bench test with torch and a DMM )? :mad1:

a narrowband o2 can't really target 15.8:1, so if your trims are truly landing you at 15.8:1:

- messed something up in your bin regarding o2 configuration
- o2(s) is(are) bad
- o2 wiring or ground or something is bad
- the 15.8-16.1:1 has a measurement error.

my hunch says its the last one