HP Tuners Tutorials

[Gregski]

HP Tuners Top Tip # 47

If you were away from HP Tuners for a while like I was (looking at you COVID-19) and now you may be thinking of doing some more tinkering, you may find this tip useful.

Say the last time you tuned was six months ago or a year ago, and now you want to change something else. Well if you are like me then you may wonder where did you save that last file to? Is it on your office PC that you upgraded since, or on your laptop that you loaned to your daughter for school?

In that case the best thing to do is read the configuration from your PCM like we did in the very first tutorial, so simply refer to that and follow those steps, and I recommend you call it something like 000 - Baseline 03-21-2021 that way you will be certain you will pick up from where you left off, since sometimes your latest file may be something like 15 - Tried Something That Didn't Work and then you forget that you went back to 14 - Last Known Good Config

yes that has three leading 000 in it to signal a new series of tuning a new chapter if you will, but you do you

[MDPotter]

Glad to see you back adding to this thread!

[Gregski]

Originally Posted by MDPotter

Glad to see you back adding to this thread!

Thanks mate, it was bugging me that I left it unfinished!

[Gregski]

Part IX - Enable Power Enrichment aka Accelerator Pump / Secondaries

Let's take a look at some Channels that can help us gauge first if Power Enrichment is even coming on, and then how much it is effecting our Air Fuel Ratio and when.

To do this we need a minimum of three channels, so we'll start with those and then add some more for better context.

Throttle Position channel (so this is the throttle blade position on the nose of your engine, and not the actual throttle pedal, since some of us may still have drive by cable, meaning non electronic throttle pedal)

Equivalence Ratio Commanded channel (this is the adjustment that is being made to our Air Fuel Ratio, so since we are dealing with Power Enrichment it will always be the amount we are enriching) we can choose what units to show this in, either Lambda or AFR. If we choose lambda it will show the value of 1.0 until PE kicks in then it will drop below 1.0 to something like .85 to show a richer fuel mixture. In other words when we are just cruising the system says lets take our perfect AFR of 14.68 and multiply it by 1.0 and that doesn't change anything cause one times four apples is still four apples type of thing. Again the cool kids tune in Lambda but I can barely wrap my head around AFR. It doesn't matter which units you use as long as you're comparing apples to apples.

Air-Fuel Ratio Commanded channel (this is the actual final result after all the adjustments, this shows what Air Fuel Ratio we are running at this particular moment in time, if Power Enrichment never comes in then we strive for a perfect Stoich ratio of 14.68, which is a theoretical number that says 1 shot glass of pure(ish) gasoline requires approximately 14 and a half shot glasses of air to burn at it's best)

[Gregski]

Part IX - Enable Power Enrichment aka Accelerator Pump / Secondaries

Now to get a better perspective and to remember what it is that was happening when you go to review the log an hour later or a week later, I like to add a few more helper channels if you will

Engine RPM will tell us when we shifted gears

Vehicle Speed obviously tells us that we've tickled the skinny pedal

feel free to add what ever channels will help you out analyze things, just keep in mind the more channels you add the slower the data transfer may be as you log

[Gregski]

Part IX - Enable Power Enrichment aka Accelerator Pump / Secondaries

So we could stare at the values in these channels in the left pane of our HP Tuners Scanner but things really paint a better picture when we add a Chart vs Time to our layout in the right hand pane.

So essentially the Channels are just a way of capturing the data we need and not having to bring in all the other noise, but we really analyze things on the right hand side of the Scanner screen.

Let's take a look at a couple Chart examples, this first one simply illustrates starting from the top, that we just shifted from 1st to 2nd (top RPM red line) the middle orange line shows us building up some speed, and the bottom green line shows how we were at Stoich AFR and then dipped into Power Enrichment and richened the air fuel mixture to 12.26 proving to us that Power Enrichment indeed kicked in.

You can start by adding these channels and creating these types of simple charts prior to making any Power Enrichment changes to your tune, and you will see that that bottom green line never dips for you, well unless you go nuts and hold your gas pedal down to the floor for a second above 5,000 RPM, not recommended, and not safe out on the road

[JamieGallien]

Gregski, Thank you so much for this! I have a 65 C10 SWB with a 5.3/A4 that I am almost ready to test the fuel system and fire up for the first time. I had my pcm wiped/prepped by a mail order guy. I took the time to copy/past and make a PDF with all of your steps so I can read offline. Rest assured I will be going through your steps to make sure everything in my PCM is right.

[Gregski]

Originally Posted by JamieGallien

Gregski, Thank you so much for this! I have a 65 C10 SWB with a 5.3/A4 that I am almost ready to test the fuel system and fire up for the first time. I had my pcm wiped/prepped by a mail order guy. I took the time to copy/past and make a PDF with all of your steps so I can read offline. Rest assured I will be going through your steps to make sure everything in my PCM is right.

Awesome, use the compare feature I mentioned somewhere early on or reach out to me and we can text or IM if you have any questions, a lot of those tuner guys/gals are really good the problem is they don't have the access to your actual vehicle they can not go for a ride along with you with their laptop in their lap and log any data, that's where the magic happens

[jjzepplin]

SOOO Glad I just found this thread! And Thank You for posting it! I just received my HP Tuners kit and have two trucks to use it on. 2014 5.3 6l80 Sierra SWB and my 72 Blazer 5.7 T56. The Blazer still needs a fuel system so I can tinker with my Sierra and disable the AFM DOD and maybe a set of headers and exhaust. I have not read all the posts here yet but am working on it. I am guessing I am going to need a few thumb drives...

[Gregski]

Originally Posted by jjzepplin

SOOO Glad I just found this thread! And Thank You for posting it! I just received my HP Tuners kit and have two trucks to use it on. 2014 5.3 6l80 Sierra SWB and my 72 Blazer 5.7 T56. The Blazer still needs a fuel system so I can tinker with my Sierra and disable the AFM DOD and maybe a set of headers and exhaust. I have not read all the posts here yet but am working on it. I am guessing I am going to need a few thumb drives...

Thanks mate, not sure how your post got by me, always happy to hear about another HP Tunerista. Just so you know the 2014 is a bit of a different animal than the Gen III 1997-2007 LS engines this tutorial was written for. Yours is a Gen IV and I think its a bit more complicated especially when it comes to the ignition timing tables as they introduce virtual timing curves, etc. Also I think the PCMs are different and use different plugs.

Anywho, can you customize your tunes on stock OEM cars in Florida, I know we can't here in California cause of our bianual SMOG checks?

[jjzepplin]

Thank You. For now, I am just doing a few small things to the 2014. Headers and AFM delete. Oh I know about those smog laws. I spent the first 30 years of my life in Cali. I am originally from Oakland. I used to make the majority of my hustle cash getting hotrods to smog so people could enjoy them.

[BigCountryx]

This is exactly the type of writeup I needed to get me going. I've been having HPTuners for 8 years and have been too scared/confused to commit to it. I've been paying for tuning that whole time haha. Well, my guy has hung it up and retired from tuning, so I stumbled across this thread at the perfect time. Thanks, Gregski, you're the man. I've just pulled the file from the pcm/motor I have for my next swap and already feel like I've got it to the point it's ready to fire.

[Gregski]

Originally Posted by BigCountryx

This is exactly the type of writeup I needed to get me going. I've been having HPTuners for 8 years and have been too scared/confused to commit to it. I've been paying for tuning that whole time haha. Well, my guy has hung it up and retired from tuning, so I stumbled across this thread at the perfect time. Thanks, Gregski, you're the man. I've just pulled the file from the pcm/motor I have for my next swap and already feel like I've got it to the point it's ready to fire.

You're welcome I appreciate the kind words, have you seen the crazy nonsense I am working on now My Dusty 71 GMCe Electruck

[MTC_959]

Originally Posted by Gregski

Thank you
Are you asking me if there will be an article on how to calibrate the MAF? Or are you suggesting you want to post one up?

This method uses the Short Term and Long Term Fuel Trims (STFT+LTFT Maths) to calibrate the MAF and does not require a third party Wideband O2 Oxygen Sensor, it will be covered in greater detail in the Tuning Series of this Tutorial, coming soon, but for now here are the basic steps.

Step 0. Save your existing configuration file as something like: 00 - MAF Calibration - Initial.hpt this is your current working setup, if things go South you can always go back to this.

Step 1. Disable the MAP sensor. In VCM Editor go to Engine \ Airflow \ Dynamic \ Dynamic Airflow and set the following two values to something like this:

High RPM Disable 100
High RPM Hyst 10

Step 2. Disable DFCO. In VCM Editor go to Engine \ Fuel \ Cutoff, DFCO and set the following value:

Enable ECT 284

Step 3. Disable Catalyst Protection. In VCM Editor go to Engine \ Fuel \ Temperature Control \ Catalyst Protection and set the following:

COT Disabled

Note: We do this as part of the Standard Housekeeping procedures, but it doesn't hurt to check.

Step 4. In the VCM Scanner make sure you have added the following Channels:

Mass Airflow Sensor (not to be confused with the Mass Airflow channel which shows grams per second)

Short Term Fuel Trim Bank 1 (SAE) if starting with the default channels this channel should already be there
Short Term Fuel Trim Bank 2 (SAE) if starting with the default channels this channel should already be there

Long Term Fuel Trim Bank 1 (SAE) if starting with the default channels this channel should already be there
Long Term Fuel Trim Bank 2 (SAE) if starting with the default channels this channel should already be there

Step 5. In the VCM Scanner create an AFR % Error graph based on the Mass Air Flow Frequency sensor.

If you don't see the graph pane already on the right hand side, go to Layout \ Add To Layout and select Graph

Right click anywhere in the graph pane and click Graphs Layout to bring up the Graph Display Layout Editor then click the green plus sign Add Graph icon on the menu bar, make the following selections:

Parameter: LTFT + STFT [Math]
Decimals 2
Cell Hits Required: 5 (or what ever you like)

Shading
High Value 20 Color: Red
Low Value -20 Color: Green

Column Axis
Parameter: Mass Airflow Frequency [Sensor]
Values:1500 1625 1750 1875 2000 2125 2250 2375 2500 2625 2750 2875 3000 3125 3250 3375 3500 3625 3750 3875 4000 4125 4250 4375 4500 4625 4750 4875 5000 5125 5250 5375 5500 5625 5750 5875 6000 6125 6250 6375 6500 6625 6750 6875 7000 7125 7250 7375 7500 7625 7750 7875 8000 8125 8250 8375 8500 8625 8750 8875 9000 9125 9250 9375 9500 9625 9750 9875 10000 10125 10250 10375 10500 10625 10750 10875 11000 11125 11250 11375 11500 11625 11750 11875 12000

Label your new graph something like: MAF Calibration (box at the very top)

Step 6. Save your new configuration file as something like: 01 - MAF Calibration - Setup.hpt this is the tune you will need to flash to your PCM in order to disable the components mentioned above only while you collect the MAF data. Flash your PCM with this file.

Step 7. Warm up the truck and then go drive around with your HP Tuners laptop hooked up for 30 minutes avoid wide open throttle acceleration and log your data. In my daily driver I like to log my trip to and or from work, that way I ensure the MAF is calibrated for the cells I am sure to hit on my most common drives. After the drive stop the log and save it. You will be able to replay this file in the comfort of your own home and safely watch what happens in the graph we created in Step 5 as opposed to glancing at your laptop on the passenger seat of your car while you drive.

Step 8. After your drive copy the data from the graph that we created in Step 5 in the VCM Scanner to the file in Step 0 in the VCM Editor (the very first time I calibrate a MAF I like to do a Paste Special Multiply by %) and save it as a new name 02 - MAF Calibration - First Mods.hpt This file will do two things for you, one it will re enable the MAP sensor as well as the DFCO and write the new MAF calibration to the PCM, and we want to do exactly both of those things. On LS Swaps I leave the Catalyst Protection (Step 3.) off.

GREETING TO ALL

can anybody explain or add some photo to keep this lesson clear for me.

thx.