Intro to ECUFLASH Tuning for Mitsubishi Stock ECU
Welcome to another blog post from me, Oliver.
We will look into something I have been into for a fair few years now: Tuning of Engines without the expenditure of buying an aftermarket programmable engine management system, or ECU.
Have you ever wondered why in today’s modern world with computer technology being spectacular even in the 1990s, People often still opt to spend a lot of money; generally $2000 + and time to re-wire the car to suit a new ECU just to make some basic adjustments, and end up having to calibrate the whole engine mapping, including every sensor and setting from scratch?
In the case of a stock ecu that cant be tuned, this is the ONLY option to get a custom turbo kit, or highly modified engine to run safely. I have done this many times and its not for the faint hearted!
Although it has some benefits, the pros and cons do not add up for a lot of people.
Credit goes out to all the developers who worked to make the base for this Open Source, without them you would be looking at a 3 grand bill for an ECU, Wiring, and Tune.
Thankfully the factory fitted unit is VERY powerful once unleashed!
So here i present the solution: Plug in a Laptop and directly edit the settings on the original unit for a few hundred bucks!
Saving $$$ while modding, Gotta love that!
Pre Warning
Sounds easy right? ehhh, kind of... Engine Calibration or the “Tune” is nothing short of mind boggling for many people and mistakes can be costly so proceed with caution. A degree or 2 too much of Ignition timing and BANG! , Goes the rod out the side of your engine block. Better grab a box of tissues, for your tears and the pool of oil left on the road!
It took many years of testing and learning until I am happy enough to be able to offer this information as a guide to others, aswell as offer my services such as BASE MAPS & E-Tuning with confidence.
Being a Trade Certified Mechanic and previously operating a full custom car and performance workshop did help a lot with background knowledge speeding up the learning process, but it can all be learnt with enough time and commitment.
Safety Notes:
-Ensure your laptop has a good battery and a reliable USB Port. - a dodgy port connection or unexpected shutdow can “Brick”the ECU meaning it is unable to be used or rewritten.
Extreme caution must be taken when flashing the file onto the ECU.
-Errors in Definition files, Flashing of wrong software etc will result in a bricked, useless ecu that cannot be recovered in most cases. - if you are unsure DO NOT PROCEED!
Software:
-OpenEcu ECUFLASH
The main re-flashing & editing tool that supports an ever-growing list of vehicles. EcuFlash sends and receives data via the OBD port. also allows you to edit ECU data (known as 'maps' or 'tables') in a human-readable format using a XML-based definition system to translate the data.
With properly setup definitions, the ROM from any vehicle can be edited.
https://www.tactrix.com/index.php?option=com_content&view=category&layout=blog&id=36&Itemid=57
- EVOSCAN
The only Data Logging software compatible with our ECU, specifically built for this Purpose by a fellow Mitsubishi Enthusiast.
https://evoscan.com/
- Mega Log Viewer
Datalog analysis software that makes viewing logs much easier and quicker than just reading from a list of numbers spat out by EVOSCAN.
https://www.efianalytics.com/MegaLogViewer/
Hardware:
-TACTRIX OpenPort 2.0 USB to OBD adaptor
-ReFlash Connector for your Specific Vehicle
Compatible ECU Type and models: Unfortunately only models with publicly available definition files can be tuned easily for free. This is called “Open Source” or “Donationware”
If no XML file is available, the only option is paying a professional programmer to build the definition file for you, or attempting to learn 8/16bit Hexadecimal Computer Code.
Errors in these files will cause an array of problems, it is not a simple task and not suitable for anyone to go in there and try to make willy nilly changes. unless you are very experienced, DO NOT ATTEMPT.
Tuning Files:
-Definition Files (.xml) ( Think of this as a roadmap to display information )
-ECU Calibration ROM file (.hex or .bin) ( The actual HEX Code file the ECU operates from )
For the first basic example, lets assume you want to make minor changes to a rom file that has some basic tables already been defined, Such as a Mitsubishi Lancer 4G93 1.8L engine 99-03 AUDM.
Guide Steps:
1 - Download and install ECUFLASH
2 - Download .XML File that matches the car you wish to tune
3 – Open .XML File in Notepad , Check the Section where it says: <memmodel>H8539F</memmodel> this is the CPU memory chip type. This should be changed to whatever your actual ecu has installed. So remove the ECU from the car, and pop it out of its Black Plastic Case.
*** If you find you have a Metal Case, your ECU is the older model 1996 -1998 and NOT TUNEABLE. ***
Close up view of the ECU Motherboard for a 4G93 fitted with a MH7203FA CPU.
Look at the large Square Chip on the Circuit Board, this is the CPU. You will see a part number on it:
Either MH7202F or MH7203FA. if the xml file is F and your chip is FA, just add the A and save.
The xml file should be edited to match the chip. like so:
Change: <memmodel>H8539F</memmodel> to <memmodel>H8539FA</memmodel>
Save .xml file.
If this is done incorrectly, say goodbye to the ecu. It can now be used as a door stop and thats about it.
4 - When you have edited the .xml file, save and place it in the file directory that ecuflash has been installed into.
Example : C drive/programfiles/openecu/ecuflash
Paste it into the folder: rommetadata
5 - Open ECUFLASH and plug in the Tactrix cable to the OBD port and the re-flash connector under the steering column, turn ignition on but engine not running.
6 – Select the Car/ECU type that matches the CPU code you found earlier.
7 - The READ button at the top will illuminate blue, click it and confirm - loading bar should appear, do not disconnect or turn the key off until it reaches 100% and the success confirmation message appears.
8 – When READ completes the ROM file should open up in ECUFLASH and tables will be visible to view and edit!
Only tables defined will show up here, but there are many more that have not been discovered. This particular car only the basics are available, but the Lancer Evolution has around 10 times the amount.
9 - SAVE THE ORIGINAL FILE as .BIN. Give it a name and store in safe place before making any changes –
It contains the immobiliser code, the data is set differently for each car.
9 - Test Write when edits are complete to check your setup is correct and hasn’t corrupted the file.
-Click the Blue TEST WRITE button. - loading bar should appear, do not disconnect or turn the key off until it reaches 100% and the success confirmation message appears. if this completes successfully now you can comfortably flash the file permanently. (finally!)
10 - FLASH the new file by clicking the Red FLASH Button. - Take even more caution with connections and battery level etc as this is the really dangerous part!
When loading bar completes you are done!
Now Start the car and test! - If you purchased a base map from me, it will fire up and run just like stock.
The process of Datalogging and making further changes can now be done to fine tune it.
This is a super quick write-up to explain the basics of setup and flashing method to help out some fellow Mitsubishi Enthusiasts, I hope it helps!
Be sure to check back for more in depth write ups on Data Logging, Advanced Tuning, Speed Density Conversion(MAF Delete), Motorsport features, like Launch Control and Flat foot shifting.
Modified tune files such as Turbo Base-Map, and High octane tunes for N/A running on 98 octane, are Available in the Shop. Please contact to discuss custom tuning options :)
Good luck and Happy tuning!
Our old Mirage work car back in 2019 - The supply run workhorse & ECUFLASH testing rig.
The 4G93 engine swap helped haul loads of parts much faster, and allowed me to develop the understanding needed to safely Re-flash these ECUs and offer it as a service to others.