Hello folks! I am really happy to announce you that, after I beg Alexander from Moscow via mails and phone, he finally made the English version of the Ecueditor for mazda V6 engines and I really want to say him: THANK YOU.
Now it will be easier for you to understand the whole thing.
*DISCLAIMER* Do not attempt this if you don’t know what you’re doing. Also, if you haven’t proper equipment to monitor the changes: Wideband and knocking sensing devices.
After installing a socket into the board in place of the existing EPROM 27c256, like showed in part 1, you need to read the content of the desoldered EPROM.
In case you damaged it, you could still manage to find a basemap online, but I strongly suggest you to take care desoldering the original chip.
To read the EPROM you need an EPROM/EEPROM programmer, you can find plenty online just make sure it can read and write 27c256/27c512 chips.
After you estrapolated the binary file from the EPROM, which should be 32kbyte in size, you have successfully read your ECU software in which you will find our beloved maps. Please note that the stock EPROM cannot be erased. So you need to source a new, deletable, chip in which you will be able to burn a new map.
To modify it, you could use a simple hex editor, but you should know where the fuel maps, ignition maps, rev limiters, vris switchpoints are.. In order to do so, you should disassembly original ecu file, understand the software and then you’ll know where these maps are.. This would take A LOT of time and efforts.
Thanks to the wonderful people who sometime populate internet, in particular to ALEXANDER from Moscow, whose nick is Berserk, we are a software to locate basic maps easily. I had the chance to chat with this wonderful guy, and he promised me he will do an English translation of the software, but meanwhile, I translated it and made some pictures to explain how to use it.
Feeding the file to the editor
Download editor: it’s a portable editor written in non-unicode language that will be most likely displayed in small squares instead of russian language. You should set russian as a non-unicode support language, follow this very helpful guide but instead of Romanian, use Russian: Change system locale
Open the portable Editor and you will find this (Of course in russian):
Click in open, feed it with your ecu binary.
In the notes, you will find what the ecu firmware is, so you can select in the dropdown menu: FW version.
If everything went smooth and the ecu file is fine with the correct checksum, in the top right checksum box you will see the same value as expected checksum box, which usually is AA55.
On the VRIS tab, you will find RPM setpoints for each butterfly valve for each given load: Low load, Medium load, High load, which can be selected from dropdown menu. Green is Open, White is close.
In the other tabs you will find Fuel maps, Timing maps for high octane or low octane fuel (knock sensor interpolation), multipliers and rpm limiters.
I will not tell you how to interpret or modify these maps because it would be too easy. Get a wideband and aknock sensing device and start modifying and verify what the changes do. Please don’t make big changes all at once as this could lead to engine knock and engine failures if not done properly. You can help yourself downloading and comparing different mazda v6 ecu maps (here’s my archive: download).
*IMPORTANT* In order to make the car start and drive fine with no strange errors you should correct the checksum doing the following before saving the map binary:
Click on box “Check Checksum“
On the box next to it click “Calculate“
Click again on box “Check Checksum” and make sure it now shows the same as “Expected checksum” usually AA55 Hex value.
Now Save and enjoy.
Burning the EPROM
Now what you have to do is to burn the modified binary into an EPROM (27c256, 27c512). Please understand that if you’re using a 512K memory (64Kbyte size), you should write the software in the second half of the chip memory. Starting at address 0x8000.
Install the freshly burnt chip into the socket you soldered following part 1 and you’re good to go.
If you wish to delete the content of the EPROM in order to write a new software in it you need an UV Eprom ERASER, don’t even bother trying nail uv ovens. Alternatively, you could use a compatible EEPROM (W27c512) in place of the 27c256. These are faster to delete because they can be erased directly from the programmer and allow you to do many modifications without having to wait the UV Eraser to delete your chip (Usually 30 minutes).
I also discovered there are many other values which could be tweaked in the firmware to make the stock ecu feel a lot more like a full standalone. Sadly, I have no time to extensively analyze the firmware and code an editor; also, since full standalones became cheaper, I suppose that it’s not worth the effort to do so. So, at the end, now you can do a basic remap, adapting fuel to the breathing mods you’ve done and optimize spark timing and rev limits for your application, the tables that the editor shows should be enough to allow you to optimize a mildly modified engine, of course it wouldn’t allow you to run a boosted engine correctly.
Feel free to contact me to add or modify something in the above guide.
626/MX6/MX3/323/X6/X9/Ford Probe 91-95 ECU REMAP – Part 1 – Chipping the ECU.
The mazdaK series V6 engines still live and will continue to live as they are pretty stout and reliable engines.. These good sounding engines also deliver good power to the wheels but.. We, car enthusiast, always crawl for more power. What if we want more power? of course if you have a 1.8 Liter V6 engine (K8, K8-DE, K8-ZE) the best solution would be an engine swap to a KL-DE (KLDE) or KL-ZE (KLZE) but if you already have a 2.5 Liter engine or you wish to stay 1.8 you can have a solution: Remap your ECU. To remap your ECU, you need to “chip” an Obd1 ECU.
First of all, i want to say THANKS to Alexander Moskalev from Moscow since his hard work on these ECU is what made the remapping possible. He, I believe before anyone else, reverse engineered those ecu to locate the parameters we can today adjust. Further research has been done by me thanks to my friend Antonio who provided me the car to work on.
While the gains are somewhat limited compared to a full standalone it can be done. This of course, only if you stay naturally aspirated, for forced induction you definitely need a full standalone ECU.
Benefits of ecu remap:
The main benefits of the Mazda v6 ecu remap are:
Run a 2.5 Engine on 1.8 ECU with the correct fuel and ignition timing.
Use any VAF (mass air flow sensor aka MAF) with any obd1 ECU.
Change the VRIS engagement and configuration (Variable Resonance Induction System) to increase low and midrange torque.
Change RPM Limiter.
Adjust fuelling and ignition timing to compensate for breathing mods and to increase power.
Which ECU are eligible for remapping?
Any obd1 ECU that stores the maps in the 27C256 Eprom is virtually chippable, the one that I know of are: KL31, KL01, K819, KL07, KF11, KL55, KL86. For these ECUS I can provide stock firmware to study purposes or to program it into any ECU.
Let’s begin: Chipping your ECU. *You need soldering skills*
With chipping i mean to replace your EPROM with a dip28socket, on top of where you will put your EPROM (27C512 or 27C256 or EEPROM equivalent). Stock EPROM (27c256) doesn’t have a window to UV erase it, so we need to replace it with one that allows you to erase it with the aid of an UV EPROM ERASER.
First of all, remove the ECU from your car, mine was a OBD1 K819 ECU.
Open your ECU taking care to not break anything, an antistatic wrist strap would be good to wear to not damage any component with static electricity discharge.
Now locate your EPROM. You should be able to read “27c256” on the body of the integrated circuit.. These chip contains the firmware of the ECU. Now prepare yourself because you need to unsolder it and unsoldering it will require good skills and patience.
To correctly desolder it you need several tools:
Desoldering vacuum pump
If you have never done soldering work on eletronic boards I suggest you to do some practice on other scrap boards before attempting to desolder one of these components, because these are really a pain to do. I could also recommend to go to a professional but.. That’s a good reason to learn soldering. Heheh 🙂
After your EPROM is desoldered, you need now to solder a DIP28 Socket in order to allow fast insert and removal of the custom EPROM.
Those sockets and erasable Eprom are easily available through internet, before attempting to chip your ecu, make sure you have like 3 or 4 of these, because you could damage these in the process, especially if you are a novice in soldering.
Be careful when removing the eprom from the socket and when placing the socket through the board holes as the pin can easily bend.
After the ecu is chipped (socketed eprom slot) you can either: buy an already tuned chip (I could provide some depending on the application), or develope your own map using a wideband air fuel and a knock sensing device or a dyno. In order to develope your own map you must understand EVERYTHING about the engine and combustion process. I will make some post explaining the basics but since you can make big damages if you make a mistake please avoid if you don’t feel confortable changing ECU parameters.
For this post is everything, the part 2 will explain what you need to program the EPROM and what you can really do by tuning the ECU firmware.
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