LS1/LS2/LS3/LS4/LS7 etc. - LOGGING, ADJUSTING INJECTOR SLOPE

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06MonteSS
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LS1/LS2/LS3/LS4/LS7 etc. - LOGGING, ADJUSTING INJECTOR SLOPE

Post by 06MonteSS »

DISCLAIMER: My car is a 2006 Monte Carlo SS with the 5.3L LS4, and I am using Predator model U7191. The instructions that follow are based on my personal experiences, several hours, days, months spent learning the ins and outs of tuning my own car with my Predator, and also from information I have collected from other online users as well as from the folks here at Diablosport. While these instructions should apply to other engines/platforms, I titled it as for LS4's since that's what I have. Even though we may have the same car and/or engine, every one of them is different and will not run exactly the same - what adjustment percentage that works for me may not work for you, you could need less or more. I am not responsible for any issue or damage that occurs to your vehicle by your own tuning adjustments. You are responsible for your own actions and do so at your own risk. While MY car now runs like a bat-outta-hell, as well as some other people's that I've helped and continue to help - your mileage may vary, as they say. Now, on to the goodies...

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ITEMS YOU WILL NEED FOR THIS CLASS: (LOL)

To log data and view the results on your PC, you need to have the power adapter and serial (or usb) cable, and download the Dataviewer application from Diablosport's site and install it on your PC. You'll also want to download and install DSLogRedux to analyze your .csv log file afterwards and get the recommended adjustments to make to your tune.

DSLogRedux can be found at http://www.dslogredux.com (3rd-party app! Not a Diablosport app!)

For DSLogRedux support info, click here!

Be sure to subscribe to our mailing list to receive e-mail notices for new updates and information regarding DSLogRedux!

Also, if you find our application to be a useful tool in your tuning regimen, please consider donating! This will help us to continue to support our website and future application development – that we are now trying to do out of our own pockets and personal time. Thanks!

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INSTALLING A TUNE:

The first thing we want to do is to install one of the "No DOD" tunes (for Monte/Impala/GXP LS4's only) - either the "Diablo Tune No DOD" (for 93 octane) or the "91 Octane No DOD" tune. If your truck/other vehicle not listed above has DOD, then you need to go into Modify Tune and turn off the DOD manually.

The reason we want one of the No DOD tunes is because I have seen the log/data numbers be really screwy when the DOD kicks in, and it makes it more difficult to go through the log and figure stuff out. After your car gets dialed in, you can then install a tune with the DOD still enabled if you wish, and just apply the same adjustments that were made to the No DOD tune.

So anyway, after the No DOD tune is installed, drive for about 50-100 miles to let the ECM re-learn and settle in the new adjustments the tune has made. For those of you who don't have a DOD (displacement on demand) equipped vehicle, just install the Diablo Tune (which is for 93 octane) or the 91 octane tune - or trucks have the option of an 87 octane tune.

If your vehicle/Predator only has a "Diablo Tune" (or "Performance Tune") and an "87 Octane Tune", then your Diablo/Performance tune is for 91 octane or higher.

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LOGGING:

Now, before we start making any adjustments to anything, we need to get a log of what your car is actually doing with the fueling.

NOTE: You want to have been driving the car for about 15-20 minutes before you start to record a log, so that everything is up to normal operating temps.

To do a log, here's what I do...

I start up my car and let it warm up for about 5 minutes, and with it already running - I hook up the Predator. Let it boot up, and then select the Diagnostics menu. Then choose the Real Time Data menu, then select the "gas general short" option (less items to scroll through compared to Complete), then on the next menu, choose the "select from a list" option. This will give you a list of all the parameters it can log. Use the up/down keypad arrows to highlight a parameter to log, then select it by clicking the center button... it will put an asterisk next to that parameter to show you that it's selected for logging. then scroll down through the list and select any others you want to log. Some of the parameter names are long and you can press the right arrow button to have the text scroll to the right so you can read it. Remember, the less you select to log, the better the log will be - because you will get a better/faster sampling rate and a longer log. With the parameters I list below, I am able to get a good 20-25 minute log file with the 7191 predator.

If you have a 7194 model predator, you will only be able to log for about 1.5 - 3.5 minutes - this is normal for those models.

Here's what I log:

air fuel ratio (Equivalence Ratio) *
commanded throttle position (or Absolute Throttle Position) *
engine speed (RPM) *
intake air temp
long term fuel trim bank 1 * ***
MAF Sensor Mass Airflow
MAF Sensor Frequency
spark advance
total knock spark retard

* -- these parameters are REQUIRED in order to use the DSLogRedux application!

*** For those with dual exhaust - i.e. two CAT's, and 4 O2 sensors (gto's, vette's, trucks, etc), you'll also need to log "Long Term Fuel Trim Bank 2"...

** HOWEVER - those of you with the older model tools - 7192, 7193, 7195, 7198 on the 9rXX revisions - you don't have the AFR parameter available - so you don't need to worry about selecting that one... when you load your 7192/93/95/98 log and verify parameters, it will prompt and ask you if the log was done with a 7192, 7193, 7195, or 7198... answer YES to that, and you'll be fine. It will still go through and filter the log correctly, based on the RPM ranges. You also do not have the "commanded throttle position" either - so you need to log Absolute Throttle Position instead


For Trinity and newer 9rXX revision Predator users, the logging/monitoring parameters are now categorized under a bunch of different sub-menus and can be a PITA to find... so user "aviraled2002" was nice enough to map them all out, so people will know right where to find 'em!! Here's the parameter location mapping:

Air Fuel Ratio (Equivalence Ratio) = Under FUEL menu

Long Term fuel trim bank 1 = under FUEL menu

Long Term Fuel Trim Bank 2 = under FUEL menu

Spark Advance = under IGNITION menu

Intake air Temp = under INTAKE menu

MAF Sensor Mass Air Flow = under INTAKE menu

MAF Sensor Frequency = under INTAKE menu

Total Knock Spark Retard = under MISFIRE menu

Engine Speed (RPM) = under PERFORMANCE menu

Commanded Throttle position (or Absolute Throttle Position - for older vehicles that don't have the Commanded parameter) = under THROTTLE menu




Once you have them all selected (and have driven for 15-20 mins), hit the ESC button until it asks you if you want to "log the data?" and choose "yes" to start recording the log. If you choose "no", it will just show you the data on the Predator screen but won't actually save it to a log file.

Now go do some good steady driving on the highway.

You need to do steady driving/cruising so that your RPM's are between 1800 - 2500! (1800-2000 is ideally where you want to be, but we allow for up to 2500 due to some trucks gearing, since their rpms could be a little higher)

DSLogRedux now allows you to select the RPM range to use for its analyzation of your logs, based on the RPM range for which your log was created. This was incorporated due to each vehicles different gear ratios, and for those who have installed aftermarket gear sets, thus altering their normal driving/cruising RPM level.

For example, if your normal steady driving/cruising is around 1900-2100 RPM's, then in DSLogRedux, you'd select the 1800 - 2200 RPM range to anaylyze your log file with. If your normal steady driving/cruising RPM's are around 2201 - 2299, then in DSLogRedux, you'd select the 1800 - 2300 RPM range to anaylyze your log file with. etc. etc...

After about 20 minutes or so (1.5-3.5 minutes with 7194 predator), you'll get a notice on the Predator screen that says the "log is full". click the center button to select "continue", hit the ESC button until you're back at the main Predator screen, then unplug it from your OBD port.

Your log is done!

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REVIEWING YOUR LOG:

To get the log off the Predator and onto your PC, hook up the power adapter and serial (or usb) cable to your Predator and let it boot up to the main menu. Now start up the Dataviewer. It'll tell you it can't read the VIN of the vehicle (duh! cus it's not connected to the vehicle LOL) and to click the download icon to get the log from the Predator. So go ahead and click that icon and wait a few minutes for the log to download from your Predator.

Once it's downloaded, you will see a list of the parameters you selected to log on the left-hand side of the Dataviewer screen. You can click the checkboxes to the left of each one to have it show up in a graph on the right side, but it's much easier to go through the data in Microsoft Excel (or DSLogRedux!). To do that, go up to the "file" menu and choose to save it as a .csv file to your PC. Then you can close the Dataviewer app and disconnect your Predator from your PC.

I and a great guy name Frank (GrumpyAeroGuy) collaborated and created/built a custom app that will automagically go through your .csv log files and show you what your average LTFT's are at and tell you what you should make adjustments to and by how much! It eliminates all of the labor of drudging through the .csv Excel file manually.

You can get it here: http://www.dslogredux.com

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USING DSLOGREDUX:

After you have downloaded and installed DSLogRedux, start the application.

At the main screen, click the "Select Log File" button and choose your .csv file that you had exported from the Dataviewer.

Next, click the "Verify Log Parameters" button - this is to make sure that you have logged the necessary required parameters in order to properly analyze the data. The required parameters, as listed in the above section, are:

air fuel ratio *
commanded throttle position (or Absolute Throttle Position) *
engine speed (RPM) *
long term fuel trim bank 1 *

If you do not have the required parameters logged, you will get a popup error window telling you so. If you DO have all of the necessary parameters, then the "Analyze Log File" button will become active.

So, click the "Analyze Log File" button, and in about 3-5 seconds, you'll have your results!!

Once it has finished analyzing your log data, it will go to the "Recom. Cruise Adustments" tab and show you the results of your normal driving/cruise data. It will show you your average LTFT's, other info as well, and also tell you what you should adjust your injector slope to!

You want to adjust the injector slope in order to get your fueling dialed in correctly - so that your average LTFT's are in the 0 to -2 range.


On to the adjustments!

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ADJUSTING INJECTOR SLOPE

Adjustments are made when you re-install a tune. When you choose the tune to install, you would select "Modify Tune" instead of install tune. After changing a parameter, you press the ESC button to back out of a parameter menu, and when you're done, keep pressing it until you get back to the screen where it will ask you if you want to "Install Tune Now?". Select "Yes" and it will re-install the tune with the adjustments/changes you made.

The injector slope adjustment is used to bring the LTFT's in line to where they should be. For example, if your average ltft was +6%, then you would change the Injector Slope setting to -7%. With the injector slope now set to -7% to compensate for the +6% ltft's we had, this should effectively put us right in the range we want to be in.

You want to adjust the injector slope in order to get your fueling dialed in correctly - so that your average LTFT's are in the 0 to -2 range.

Going NEGATIVE on slope tells the ECM that your injectors are SMALLER and to spray MORE fuel.

Going POSITIVE on slope tells the ECM that your injectors are BIGGER and to spray LESS fuel.

Therefore, we want to adjust the slope before we adjust the PE ranges, because slope adjustments WILL affect the WOT/PE fueling.

After you make an injector slope adjustment, you will want to do another log to verify the average LTFT's again. Drive for about 30 miles to let the adjustment settle in and get re-learned by the ECM, then do another log following the info up in the LOGGING: section above.

Save out that new log to a .csv file and run it through DSLogRedux. If everything is in order, it will tell you "No adjustments necessary" in the "Recom. Cruise Adustments" tab.

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ADJUSTING PE (POWER ENRICHMENT):

You need to do a good WOT data log now. When doing WOT logs, you would log the same parameters as you did for the steady cruise log. To get a good WOT log, you want to start from a dead stop if you can, or at least from as slow of a roll as possible. Then, just GET ON IT!! Pretend you're on a drag-strip racing someone - get a good launch - then hammer-down and go for as long as you can, through as many gears as you can. BUT, BE SAFE!! And only do one good WOT run per log - so, after the WOT run and you're coasting down, you either continue cruising until the log is full, or you can press the ESC button on the Predator a few times to get back to the main menu to exit the data logging and it will save the log.

NOTE: Ideally, to check your AFR at WOT and adjust your WOT/PE fueling, you should use a wideband O2 sensor. But if you don't have one (I don't either), this will get you close and in a safe range so you're not too lean at WOT.

INFO: After speaking with the fine tune programmers here at Diablosport, and having another buddy dyno tune his car with a wideband and comparing that AFR to the Predator's AFR - it has been found and stated that the Predator AFR value is pretty damn accurate (for N/A cars). Based on this information, I now tune my PE settings based on the AFR value, not the stock narrowband O2's - since they are not accurate at WOT and it made me pig rich when I did. We want to have an AFR value between 12.5 to 12.6.

For the initial PE adjustment, I would go half the amount of the slope adjustment you made. So, if you adjusted your injector slope to -6%, then I would go -3% for the PE settings. Then do a new WOT data log and see what the AFR is reading at 100% throttle position... then re-adjust the PE settings as needed.

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END OF CLASS


As I think of anything else, I will update this tutorial, but I think this about covers it. If anyone has anything else to add or has any questions, let me know.

Thanks, and happy tuning!!
-Lew
Last edited by 06MonteSS on Tue Apr 05, 2011 12:46 pm, edited 65 times in total.
06MonteSS / DiabLew Tune
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Aaronr
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Post by Aaronr »

That sounds pretty cool. To bad my doesn't do any logging, which I think that sucks. :twisted: So if you had to write down the data while a friend drives. Would you just take the high and low readings in each parameter then average them?
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06MonteSS
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Post by 06MonteSS »

have them watch the ltft value while you are holding steady throttle, see what that number is. you don't want to take the highest and lowest and just average them, because when you let off the throttle, the ltft's will go up - so it's not a true reading since you're not on the gas.

just hold a steady throttle and see what the ltft is reading... it'll fluctate, so try to right down as many of the different values as possible while at steady throttle... once you let off the gas, don't write down anything...
06MonteSS / DiabLew Tune
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2014 Camaro SS - 2SS, RS pkg., short-throw shifter, NPP perf. exhaust, BMR strut-tower brace, Cold Air Inductions cold air intake
www.diablewtune.com -- www.diablocustomtune.com -- www.diablocustomtunegm.com -- www.diablocustomtuning.net
Aaronr
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Post by Aaronr »

Do you only watch 1 of the 02 or watch both banks? I have 4 o2 sensors 2 for each side? I know you want to watch the ones befor the cat.
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06MonteSS
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Post by 06MonteSS »

well, my car only has 1 bank (single exhaust pipe coming from the engine)... but if yours is a truck with true duals, then you would have 2 banks... so you want to watch both -- bank 1 sensor 1 and bank 2 sensor 1
06MonteSS / DiabLew Tune
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2014 Camaro SS - 2SS, RS pkg., short-throw shifter, NPP perf. exhaust, BMR strut-tower brace, Cold Air Inductions cold air intake
www.diablewtune.com -- www.diablocustomtune.com -- www.diablocustomtunegm.com -- www.diablocustomtuning.net
Aaronr
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Post by Aaronr »

Thanks for the help. :D
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06MonteSS
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Post by 06MonteSS »

no problem man!!

if you have a digital camcorder, have it record the Predator screen while logging, then you can play the video back on your PC and check out the numbers... ;)

also, since you can't save a log, and you will only be able to see 5 parameters on the screen at once, just log these:

air fuel ratio
long term fuel trim bank 1
long term fuel trim bank 2
oxygen sensor bank 1 sensor 1
oxygen sensor bank 2 sensor 1

and after you see which O2 number is the lowest, you would adjust based on that one... so if your bank 2 is lower than bank 1, then next time you log, just select the bank 2 O2 sensor and go by that one. Cuz the PE adjustment doesn't do the individual banks anyway, so we want to make sure the lowest one is brought up into the proper range.
06MonteSS / DiabLew Tune
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2014 Camaro SS - 2SS, RS pkg., short-throw shifter, NPP perf. exhaust, BMR strut-tower brace, Cold Air Inductions cold air intake
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mikel
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Post by mikel »

Great write-up Lewis!
I'm making this a sticky, and I'll re-title it to include LS2/4 and 07 Trucks, as these tools all have datalogging capability and have similar parameters.

Thanks
Mike Litsch
DiabloSport Brand Manager
Diablo Tech support by phone:
561-908-0040
M-F 8:00 AM to 5:00 PM EST

tech@diablosport.com
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06MonteSS
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Post by 06MonteSS »

cool, thanks Mike! will I be able to edit or add to it at all once it becomes a sticky?
06MonteSS / DiabLew Tune
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2014 Camaro SS - 2SS, RS pkg., short-throw shifter, NPP perf. exhaust, BMR strut-tower brace, Cold Air Inductions cold air intake
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Aaronr
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Post by Aaronr »

digital camcorder is a cool idea.
I was checking out the data at lunch.
air fuel ratio (i dont see this one on there on my tool)
commanded throttle position (i dont see this one on there tool)
Is there a nother name for these.

2002 chevy 5.3l
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06MonteSS
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Post by 06MonteSS »

not sure... that's what they're called on mine... got any throttle position parameters?? Relative throttle? Absolute throttle?

for air fuel ratio, how about Equivalence Ratio ??
06MonteSS / DiabLew Tune
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2014 Camaro SS - 2SS, RS pkg., short-throw shifter, NPP perf. exhaust, BMR strut-tower brace, Cold Air Inductions cold air intake
www.diablewtune.com -- www.diablocustomtune.com -- www.diablocustomtunegm.com -- www.diablocustomtuning.net
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mikel
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Post by mikel »

06MonteSS wrote:cool, thanks Mike! will I be able to edit or add to it at all once it becomes a sticky?
Yes, as soon as I figure out how to sticky it!
Mike Litsch
DiabloSport Brand Manager
Diablo Tech support by phone:
561-908-0040
M-F 8:00 AM to 5:00 PM EST

tech@diablosport.com
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mikel
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Post by mikel »

06MonteSS wrote:not sure... that's what they're called on mine... got any throttle position parameters?? Relative throttle? Absolute throttle?

for air fuel ratio, how about Equivalence Ratio ??
The U7191/4 are the only tool to display the equivalence ratio(A/F ratio).
The older tools will only display tps %.

Thanks
Mike
Mike Litsch
DiabloSport Brand Manager
Diablo Tech support by phone:
561-908-0040
M-F 8:00 AM to 5:00 PM EST

tech@diablosport.com
Aaronr
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Joined: Sun Mar 11, 2007 6:22 pm

Post by Aaronr »

Do you WOT from a dead stop?
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yuimyt
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Post by yuimyt »

I have heard/read somewhere online that after installing the modified tune, we should unplug the negative battery plug in order to reset old data that ECM learned. Do we do that every time we tune?
2009 Pontiac G8 GT / L76 powered

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