SCT LiveLink - How to Log & Analyze Your Vehicle's Data

[JoeBoomz]

If you have an SCT XCalibrater 2 or X3 tuner you can use SCT LiveLink to datalog your vehicle while it is running. After, you can analyze the data to look for issues and/or to help with future tuning, whether you do it yourself or have a professional do it for you.

These detailed data logs can help you identify fuel shortages, incorrect spark values, room for spark increases, airflow issues, and the list goes on and on. However, I have found it becomes difficult to analyze 100,000 lines of data effectively without some external help.

In this thread I will provide a quick how-to that anyone with an SCT tuner can use to log their vehicle. If you've been curious about this but thought it was too complicated or hard, hopefully this will help you out. If you've already used LiveLink, you can skip to post 2 where I will discuss how to analyze the log files.

So, let's hook a laptop to our Marauder using an X3 tuner:
Step 1: Power up the laptop
Step 2: Plug the USB cord from the handheld tuner into the laptop
Step 3: Wait for the tuner to finish booting up
Step 4: Plug the tuner OBD-II plug into the car's OBD-II port

http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/IMG_2139.JPG
IMPORTANT: if you plug the tuner into the car first, it WILL NOT work with LiveLink. The tuner needs to be plugged first into the computer.


To continue you need the ignition ON in your vehicle. You do not have to start it, but have the key in the ACC position.

After starting up LiveLink, the first step is to select which data items we want to record. Under the COMMANDS menu, we select CONFIGURE DATALOG ITEMS.
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/1%20-%20Configure%20Datalog%20Items .gif


LiveLink will attempt to connect to the car ECU to identify which data items (hereafter referred to as PIDs) are available to choose.

If you see an error message, it's because you plugged the tuner into the car first before plugging it into the computer USB, or because the vehicle ignition is not on:
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/2%20-%20Cannot%20Connect%20to%20ECU .gif


If you plugged it in correctly, you will see this:
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/3%20-%20Checking%20PIDs.gif


LiveLink will draw up a long list of PIDs that you can select from; these are the data items that will appear in your data logs:
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/4%20-%20Select%20PIDs.gif


These are the PIDs I usually log:
battery_voltage
coolant_temp
fp_duty_cycle
FPUMP_ACT_VOLTS
FPUMP_FLOW_RATE
fuel_rail_pr_psi
intake_air_tem
KNK_SEN_RETARD
load
LTFT_BANK_1
LTFT_BANK_2
maf_counts
PRES_DROP_F_INJ
RPM
spark
STFT_BANK_1
STFT_BANK_2
TCC_ACT_SLIP
TP_RELATIVE
trans_temp


You will find as you browse and select the PIDs, it can take some time. After we have made our selections, we will save our configuration so we can recall it again quickly. Under FILE we will select SAVE LIVELINK CONFIGURATION and save our PID list to a file.
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/5%20-%20Save%20LiveLink%20Configura tion.gif


With the PIDs all selected, it's time to start data logging!


To continue you will have to start your vehicle. You can log without starting the vehicle, but the data will be quite boring.

To start datalogging, use CTRL+F1 on your keyboard, or select from the COMMANDS menu START DATA LOGGING.
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/6%20-%20Start%20Data%20Logging.gif


Here's what it looks like while logging (I did not start the car). You get a nice graphical representation of the data:
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/7%20-%20Logging%20in%20Action.gif

The items that are check-marked will show up in the graph on the right. The currently highlighted one shows up yellow. The graph is useful for looking at items like fuel rail pressure that you want to normally stay constant.


Once we're done our logging run, select from the COMMANDS menu STOP DATA LOGGING:
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/8%20-%20Stop%20Logging.gif


Now we save the datalog to disk. From FILE, select SAVE DATALOG AS:
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/9%20-%20Save%20Datalog%20As.gif


LiveLink can open up data logs at any point and you can browse through the graphs in the program at any point in your datalog. This is a useful function and you can use it to check for many different situations in your vehicle. I recommend always having RPM and TP_RELATIVE or LOAD check-marked then you can identify many different scenarios (i.e., hard acceleration) and watch the data at those points.

Continued in Post 2...

[JoeBoomz]

...Continued from Post 1


After sifting through thousands of lines of data, I have built an analytical tool in Microsoft Excel with which to summarize the data. All are welcome to download it here:
http://download.ioncross.com/Datalog Analyze Spreadsheet.zip (http://download.ioncross.com/Datalog%20Analyze%20Spreadshee t.zip)
Here's what you get in the ZIP file:
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/Excel%20Files%20List.GIF

rawdata.csv is a sample datalog with 123,779 lines from two ~35 minute sessions combined of driving my Marauder. NOTE the charts shown below are not generated from the sample rawdata.csv file.
Tuner v3.xlsx is the tool created to help analyze the datalog. You will need Excel 2007 or newer to use the sheet.

IMPORTANT:
Tuner v3.xlsx is hard-coded to read a secondary file called rawdata.csv. You will have to copy or rename your datalog from LiveLink to rawdata.csv to use it.

To use the tool you must FIRST open rawdata.csv in Excel to get it into your computer's RAM, and then open Tuner V3.xlsx SECOND.

If you don't open rawdata.csv first, Excel will proceed to make hundreds of thousands of hard drive reads, which will take a substantial amount of time (hours).

At this point I will assume the viewer has a basic working knowledge of Microsoft Excel. I won't go into anything crazy, but you should be comfortable viewing spreadsheets, selecting workbook tabs, and recognize row/column references.

Here's what the data looks like that we will get out of LiveLink:
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/RAWDATA.GIF

Column A in the datalog will ALWAYS be the time in seconds since the start of the datalog. The rest of the columns are the PIDs that you have selected to datalog in LiveLink.


The Tuner sheet is set up to use Columns B and C in rawdata.csv as reference points for graphing.
Specifically, in its current format, it is looking for RPM in Column B and LOAD in Column C.
So if you want to use your own datalogs with Tuner V3, ensure you move RPM and LOAD into columns B and C as such:
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/RAWDATA%20columns%20changed.GI F
To do this, right-click on the column header you want to move and select CUT. Then right-click again to the column where you want to move it to, and select INSERT CUT CELLS. It will move the entire column to where you want it. Don't forget to SAVE the file when done.


Now that we have rawdata.csv open in Excel, we are ready to open Tuner V3.xlsx.
Warning! Opening the sheet might take up to a minute depending on your computer's speed:
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/Calculating%204%20Processors.G IF


And once it's done calculating, here's a nice summary chart of some of our data:
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/Tunersheet.GIF

Here we have a chart with LOAD along the left (vertical) axis and RPM along the top (horizontal) access. The chart is populated by data from rawdata.csv that is averaged from all of the lines in the file that meet the values in these axis.

Cell S3 allows you to select which data value you want to analyze. Currently we are looking at option H in the list at the right, which is FUEL_RAIL_PR_PSI.


Let's take a look at the formula that drives this:
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/RAWDATA%20Formula%20explained. GIF

In English, this is what the formula does to give you the value in cell G12:
1. Take the LOAD value in A12, plus and minus the value B25 (so it will take LOAD values from 1.105-0.043 to 1.105+0.043)
2. Take the RPM value in G2, plus and minus the value in P3 (so it will take RPM values from 2,550-212.5 to 2,550+212.5)
3. Average all of the FUEL_RAIL_PR_PSI values in rawdata.csv whose LOAD and RPM values meet the criteria from above #1 and #2.

The formula supports rawdata.csv files up to 900,000 in length.

IMPORTANT: Tuner V3.xlsx displays AVERAGE values over the length of your datalog. This can smooth out (but will still be affected by) spikes and dips in the data.
It is important to realize that, as you look at the chart, you could still miss important data due to the averaging.
Consider a scenario where an alternator has an intermittent charging failure and the car voltage drops during short periods. This chart would smooth out these drops and your averages would be slightly lower, but it would be possible to miss the drops entirely without looking at the data firsthand.
In Excel anything is possible and maybe one day I'll sit down and build some more formulas in that could look for something like this, but for now, this is a flaw in this averaging approach. The sheet does show the maximum and minimum of all of the PIDs at the right side, so you can eyeball any outliers there.


So what does the chart say about FUEL_RAIL_PR_PSI?
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/Tunersheet.GIF

The tune that was datalogged commands a fuel rail pressure of 40PSI, and as we see in this chart, the system averages close to 40PSI most of the time. There are some slight drops along the upper load values, especially as the RPM increases. This "could" indicate a fuel flow problem but the drops are very minimal.

So what about the values on the right side of the chart that are higher than 40? These are at higher RPM's but lower load values, which is a scenario that happens when you have the pedal down, accelerate to an RPM, then take the foot off the gas. So the engine load drops dramatically, and the fuel pressure in the system spikes momentarily as the demand for fuel in the engine drops.

Next, let's take a look at the results from the datalog for some different PIDs.
Again, Cell S3 allows you to select which data value you want to analyze.

Here's the Fuel Pump Duty Cycle, which we get by changing cell S3 to "E":
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/RAWDATA%20select%20input.GIF

Fuel pump duty cycle is a value from 0 to 1. Normal results are in the range of 0 to 0.5, and to read the values you multiply by two and consider it as a percentage. If you see values above 0.5, they are error codes being sent from the FPDM (this is something that the averaging process will smooth out and you won't see it in the chart, however you could spot it by looking at the max values shown to the right).

So we can see here in this chart that at idle (around 850 RPM with relatively low load around 0.170), the duty cycle is down at 0.19 x 2 = 38%.
The highest value we see in the chart is 0.33 x 2 = 66%.
Conclusion: there is LOTS of room left to go with this BAP-driven GT40 fuel pump!


Let's take a look at our MAF_COUNTS by changing cell S3 to "M":
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/RAWDATA%20select%20input%202.G IF

The car's mass airflow sensor (MAF) meters the airflow into the engine and we get this resulting count value.
As expected, what the chart here shows us is that as LOAD and RPM increases, the air into the engine also increases.

So how are we doing for MAF counts? Well,

According to SCT, to get good MAF resolution, your maximum MAF counts should be in the neighborhood of 80%-90% (818-920 MAF counts) of the max 1023.Looks like we're doing just perfect, with our maximum recorded airflow in the 800 range.

"But Wait!" says someone smart like RacerX, "we don't have anything showing up at 5500-6000 RPM!" Yes, we don't. There is no data in the file in those RPM/load ranges. This means I set the chart up wrong, or more likely, I didn't manage to log any events in those ranges while driving.
Consider the amount of time your engine spends in the 5,500-6,000 RPM range - it's usually for very short periods of a second at a time, if even that. Logging in these areas will be difficult unless you are doing it on a dyno.


Let's take a look at one more PID before moving on. We'll change cell S3 to "O" to look at SPARK:
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/RAWDATA%20select%20input%203.G IF

...and there are our SPARK values at the different LOAD and RPM combinations! Note that your final SPARK values are affected by a few different variables including air temperature and coolant temperatures. So averaging your SPARK values out of the term of the datalog might not be very accurate approach because these variables can change. But it's still cool to see!


Continued in Post 3...

[JoeBoomz]

...Continued from Post 2

Whew, another long-winded post. But we're not done yet!

Next I want to cover the bottom portion of this sheet, that has a secondary chart titled DATCOUNT.
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/RAWDATA%20Datacount.GIF

This chart shows you exactly how many "events" match the axis criteria for averaging. So at 0.255 load and 850 RPM, the table averaged 6,561 values! And the file we are looking at had a total of 53,628 averaged events.


Remember to take into consideration the +/- modifiers mentioned in the formula in the above post #2. The DATCOUNT table formula looks very similar:
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/RAWDATA%20Datacount%20Formula. GIF
...and if you follow it closely you will see again it is adding and subtracting cell B25 from the A-Column axis numbers to form a range for LOAD and RPM before averaging the data in rawdata.csv.


So what can we do with DATCOUNT? The values in the DATCOUNT table give you an idea of the "accuracy" of the averaging the sheet does. So with 6,000 lines of data, you know your average is more relevant than say, another cell that only has 21 lines of data.

Cell O8, "count exclusion" is a setting that you can use to exclude results with low DATCOUNT. So if you only want to review data that has a minimum of 50 points, set O8 to 50 and the values shown in the chart will become more accurate. Points with fewer lines than 50 will be excluded from the top chart.


Let's switch to a larger rawdata.csv file; check out the DATCOUNT chart on this one!
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/RAWDATA%20Datacount%202.GIF
You can see in this chart where the majority of the time driving is spent, where the DATCOUNT values are the highest. We also did manage some high-RPM data points in this run.


Next, I want to point out there are four different worksheet tabs in the Tuner V3.xlsx file:
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/Spreadsheet%20Tabs.GIF


Here's a shot of what the SUMMARY tab shows:
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/Summary.GIF

SUMMARY shows a list of averages taken from the rawdata.csv in a non-chart format. I actually built SUMMARY first when looking at the files, but found it was less useful than the charts and now don't really use it. But it is a different way at looking at the data and I left it in for anyone who might like to use it.


SmallTable is a smaller version of the BigTable tab that we have been looking at. Here's the same DATCOUNT as above, but in the SmallTable tab:
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/RAWDATA%20smalltable%20and%20d atcount.GIF

Above are the Short Term Fuel Trims from the car's O2 sensor. You can see at the higher loads and RPM's, the air/fuel ratio is less than 1, so we have more fuel than air. This is a great way to check and make sure the car is not running too rich or lean.


I actually built SmallTable to emulate the tables in SCT's Advantage III software, which is used for making tunes. One other side effect to using SmallTable is that each cell evaluates a larger range of the axis values (RPM and LOAD), because there are fewer cells in the axis, so you will have a different averaging than you will find in BigTable.


You can copy/paste directly from Advantage III into this sheet, or from this sheet into Advantage III.
With some changes to the values in the table axis, notice how similar these values start looking between our SPARK datalog and the Advantage III Borderline Knock Table:
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/RAWDATA%20smalltable%20match%2 0Advantage.GIF

http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/Advantage%20Borderline%20Knock .GIF

Notice at 0.15 load and 750 RPM, the actual SPARK values are much different than specified in the borderline knock table. This is because of the other variables that are used to calculate final SPARK, including intake air temperature and coolant temperature.


Here's an example of changing some axis values to work with Advantage III.
After you install a BAP, the ECU needs to re-learn what voltages to pass to the fuel pump in order to reach the commanded fuel pressures in the system. The problem is, every time you update the tune in the car, this re-learning has to happen again, unless you alter the tune for the new voltage values. The ECU starts off with a base voltage table and learns from there.
SO, with Tuner V3.xlsx, I am able to look at the datalog, and see what voltages the ECU is using to achieve the 40PSI pressure at the fuel rails, and then paste that into the voltage table in Advantage III:
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/Fuel%20Pump%20Voltage%20Table% 20Spreadsheet.PNG

Notice the axis PIDs are CHANGED to FUEL_RAIL_PR_PSI and FPUMP_FLOW_RATE

http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/Fuel%20Pump%20Voltage%20Table. PNG

With the axis values matching those of the table in Advantage III, I can copy/paste the new voltage values directly in and the car is properly tuned for the new fuel hardware.


So I'm at the end of what I wanted to post about this. Feel free to download the Tuner V3.xlsx file and play with it. As demonstrated above, you can change axis values or even change the axis data to PIDs other than I've done here. Don't be afraid to experiment; if you screw up the sheet or formulas, you can easily re-download it.

Hopefully some of the experts here have some datalogs they can analyze with the sheet to reveal new information about their cars that was previously unknown. If you have success with this or figure out anything else cool with it, I'd love to hear about it!

[J.bo]

This needs to be a sticky.

Thanks for the info it help me alot.

[cj7chris]

Thanks for putting this together. I have been trying to learn more and have been playing around with LiveLink and datalogging, but there is a suprising lack of information available on the interweb (at least that i have been able to find).

I'd buy a book if I could find one that went into detail.

[JoeBoomz]

Thanks guys, always good to get feedback.

I wanted to add this in:



I highly recommend using LiveLink 6.5, you can download it from http://sctflash.com/LiveLink.php

I did some digging and educated myself a bit more about LiveLink Gen2. This was the first time I've heard of it. Good luck finding it on their site today, they seem to have pulled it down.
http://images.ioncross.com/mercurymarauder.net/06-24-2012-DataloggingAndAnalyzing/Gen2.PNG

Here is a download link for those who want to try it:
http://sctflash.com/software/LiveLink_GenII.exe

Gen2 has the addition of Histograms which is the same thing I accomplish in my LiveLink post using Excel (http://www.mercurymarauder.net/forum...ewpost&t=80544 (http://www.mercurymarauder.net/forums/showthread.php?goto=newpost&t=80544))

Once SCT gets Gen2 compatible with all vehicles and tuners and makes it consistently available to the public, I look forward to working with it, then I can stop using my klunky Excel solution!

[guspech750]

Darn good info as I'm not familiar with data logging.

Thanks for posting.


Sent from my iPhone
Eaton Swap + 4.10's = Wreeeeeeeeeedom!!

[RacerX]

Very nice Joe! You've been busy! How's the car running? :beer:

P.S. Try and use PIDs in Caps whenever possible.
Other nice PIDs depending on what yer watchin:
Commanded Gear
open loop flag
Spark Advance
Spark Source
ISC Duty Cycle
Analog (if you have a wideband you want to log, add equation from drop down menus)

[IwantmyMMnow!]

Had no idea my tuner could do this....thanks JoeBoomz!

[JoeBoomz]

Very nice Joe! You've been busy! How's the car running? :beer:

P.S. Try and use PIDs in Caps whenever possible.
Other nice PIDs depending on what yer watchin:
Commanded Gear
open loop flag
Spark Advance
Spark Source
ISC Duty Cycle
Analog (if you have a wideband you want to log, add equation from drop down menus)

Bill! Always great to hear from you. The car is running perfect, like a top, and I have all the kinks worked out of it now. Now it's time to set the sights on Dad's build.

As a quick question for you - what's wrong with the lowercase PIDs?


Anyway, it might be really "tin foil hat" of me, but whenever logging I purposefully avoid any PIDs that are speed-related or that can be used to calculate vehicle speed. If I were to end up in court for some speed-related reason, such logs would provide irrefutable evidence.

So this means I avoid the PID for speed itself, and also any combination of RPM and current transmission gear at the same time.

[courtmarshall]

This is really great work. It took me almost a year to figure out what you wrote in one single post. You have given people a real jump start on the data logging and potential tuning.

Here are a couple of things I discovered on the subject.
1. There are PIDs that you can use to data log the fuel pump voltage and then correct them in the Advantage III table. There is a needed step to disconnect the battery to get the ECU to "accept" them better.
2. A good way to validate the confidence of your average (Mean) is to compare it to the calculated Median value. The furhter appart the numbers are then your data may not be "normal". Statistically if the "P" value is low then your null hypothesis of the problem must go.

[RacerX]

"PIDs are lowercase. DMRs are uppercase. These log much faster, but you are limited to logging a certain amount." Eric Brooks

"DMRs are the ones in all caps, they are more accurate and use more memory and processor than the pids which are the lower case ones." Kris@SCT

If you have a decent laptop, you get more counts/second and more accurate data with the uppercase DMRs than with the lowercase PIDs. Me. :) I'm using a dedicated laptop with 8Gb DDR3, I5, 128Gb SSD drive, W7U. Your spreadsheet analyzer is nice! I use EEC Analyzer also. One key ingredient is to have good, working O2 sensors, wideband too. Yeah, I don't usually like having incriminating data running on my laptop while I log. ;)

[TooManyFords]

This is a really good write-up. :)

[03sport007]

Sticky!!!!!!!! Please !!!!!! Thanks for posting!'!

[RacerX]

Joe! You gotta try the histogram feature in GenII! I was messing around with it to get my LWFM table correct so I don't have to mess with Manifold volume for my slight tip-in issues.

http://www.mercurymarauder.net/gallery/data/579/medium/LWFM2.jpg (javascript:;)

[O3 pharoh]

Why will my x3 not even connect? Trying everything with cords and no luck. Tried to contact act but that was a loss. Does it news to be unlocked?

Sent from my ADR6300 using Tapatalk 2

[Windsor58]

JoeBoomz,
Thanks for the great info. I had been playing around with data logging for a few years now and didn't figure out near that much. Every time I try to do it again, it takes me a while to remember how I did it before, but I think that is old age setting in...

[JoeBoomz]

Joe! You gotta try the histogram feature in GenII! I was messing around with it to get my LWFM table correct so I don't have to mess with Manifold volume for my slight tip-in issues.


Bill! Yes, it's quite a good piece of software, albeit a bit unstable. I finally got around to posting a tutorial about it here (http://www.mercurymarauder.net/forums/showthread.php?t=81526). It accomplishes similar to what my Tuner V3.xlsx does, but makes the process much easier while it isn't crashing.

I do still use the spreadsheet, because it allows for more focused averages based on the axis values. But Gen-II makes it very quick to review your datalogs.




Why will my x3 not even connect? Trying everything with cords and no luck. Tried to contact act but that was a loss. Does it news to be unlocked?

All I can recommend is ensure you are plugging the USB to the computer FIRST, and then into the car after the X3 is fully booted up (at the selection menu).

If that still doesn't work you may have an SCT driver issue. Reinstall LiveLink and it will also reinstall the drivers, and hopefully that will solve it. Failing that, you need to do a more complicated things to the drivers to fix it and hopefully SCT would be able to help you with it.

[JoeBoomz]

JoeBoomz,
Thanks for the great info. I had been playing around with data logging for a few years now and didn't figure out near that much. Every time I try to do it again, it takes me a while to remember how I did it before, but Ithink that is old age setting in...

If you dont mind me asking, what A/F ratio are you running? I just had another tune done on mine (vortec sc) and I am getting a couple too lean codes, and it failed emissions testing today (NOx too high). I am taking it back to have the guy that tuned it fix it next week, and would like to know what the target AF ratio should be. Now its running a bit over 15 at idle and gradually goes down to a hair under 12 at 4500 rpm where it stays that low til 6k+. (I was surprised to see itthat lean..) They were trying to help it get past emissions tests and I think they set it too lean. The codes come up; when I get on it hard. They dont come up if I clear them and take it easy on it. But the emissions test triggered them today. Was hoping they wouldnt get on it that hard, but they did. Anyway, any advise would be appreciated. Thanks.



Your post was edited after, but here's the A/F data if you still need it ;)

In the tune (this is SCT's base value file for blown Marauder, works great on mine):
http://images.ioncross.com/mercurymarauder.net/07-09-2012-BAP%20Wiring%20Logs/BaseFuelTable.PNG


From datalogs:
http://images.ioncross.com/mercurymarauder.net/07-09-2012-BAP%20Wiring%20Logs/AFTER%20STFT%202%20TP%20REL.PN G


Sorry I don't have any wideband data on my car yet, but multiply by 14.64 to get the values you're looking for, and good luck with the NOX COPS!

[Jeronimojc]

Great thread!

I'd like to do some AFR data logging. I wasn't sure which signals I should select. Is it the LTFT_BANK_1 and LTFT_BANK_2 signals, plus RPM?

Thanks!

[Mike M]

Old thread but great info.

[Jeronimojc]

Never mind my question. I was attempting to data log to check AFR at WOT before and after my engine swap. However, I just learned that our O2 sensors and the OBD2 data is 'Narrow Band' and useless at WOT.

[JoeBoomz]

Never mind my question. I was attempting to data log to check AFR at WOT before and after my engine swap. However, I just learned that our O2 sensors and the OBD2 data is 'Narrow Band' and useless at WOT.


Correct, the stock O2 sensors only know whether the mixture is less or more than ideal, and are not able to give you any sense of how far away from ideal you are.

You need a wideband sensor to properly log and tune the AFR. STFT and LTFT can only give you a basic idea.

[Lowndex]

Thank you for the great set of instructions.