How to Tune Your Truck with an EFI Live Autocal

How to Tune Your Truck with an EFI Live Autocal

This is a quick rundown on how you’ll flash your truck with an EFI Autocal V2 or V3. If you purchase a device and tune pack from us, in most cases we will have already uploaded the tunes onto the Autocal, so all you will need to do is flash them onto your vehicle. It’s actually a very simple process as long as you take your time and follow the steps carefully.  

Although these photos show a Cummins for reference, the flashing process will be the same across all platforms.  

Tools required:

  • Battery charger

Before you start:

  • Confirm all parts are present
  • Fully read the installation guide
  • Charge the batteries if you suspect they're low


Pulling a Stock Read File

On some vehicles (such as the 2.8L Duramax) we will require you to pull a stock read file. The stock file contains all the codes, data, software, and information needed to correctly tune your truck. It ensures that we have the correct data available to provide you with the correct tune files and removes the chance of you receiving an incompatible file.

Don't like written instructions? Check out our Stock Read video below


Step 1: Install Battery charger.

Step 2: Hook up the Autocal to the OBDII port and the laptop. 

Step 3: Open up the EFI Live Program.

Step 4: Turn the key to the ON position, but do not start the vehicle.

Step 4: Navigate to the Tune tab.

Step 5: Under the "Read" tab, select "Auto Detect".

Step 6: Then select "Read". 

Step 7: Follow the on-screen prompt to shut off the ignition and wait for the countdown.

Step 8: On the bottom of the screen, select the save button to save your stock read file

Step 9: Send your Stock File to 


Flashing Your Truck  

Notes before you start:

  • If you have a 2001-2010 Duramax Truck 2500/3500, please use the following table to remove the corresponding fuses before flashing tunes onto your truck.
  • If you have a 4500/5500/Kodiak/Topkick, you are NOT required to pull any fuses. 

Don't want to read it all? Check out the video instead! 


Step 1: Hook your truck up to a quality battery charger to ensure constant voltage for the install.

Step 1 EFI 
Step 2: Hook your AutoCal to the factory OBD2 Port (Do not tune the truck through the AutoCal OBD2 Port, hook up the AutoCal after).

Step 3: Turn your ignition to the run position and navigate the AutoCal to the Tune Tool

Step 4: Select Tuning, and then select Program Full.
*If you have an 2011-2016 LML Duramax, please select program calibration*
* if we've provided a stock file, on the 11-16 duramax, you will need to program full the stock file, then select program calibration on the tune file.

Step 5: Once the tuning is selected, it will show the Tune File. Confirm that the Six digits in the file are the same as the last 7 digits of your VIN number.

Step 6: The AutoCal will then show an "Attention". Once you've read through it, hit OK.
Step 7: The AutoCal will also require you to approve the licensing of the unit to the truck. Hit OK on the two prompts that pop up on the screen.


Step 8: The tune will now start flashing onto your truck. Once this is complete, you will see a message saying "Flash Tune File Flash Completed Successfully".

Note: If you encounter an error code during this step, please click here to view Error Code Solutions

Step 9: Hit the Check on the AutoCal and a 10-second countdown will start, turn off the truck within those 10 seconds to complete the tune flashing process.

Note: For Duramax Customers who have purchased Transmission tuning, additional steps are required. Please go back and follow steps 4-9 and select your A50 or T87 TCM file when flashing

Step 10: Start the truck to confirm that the tune file was loaded successfully and take it for a test drive.


That's it! You're done. If you have any questions, please don't hesitate to reach out to us at!