ECU tech

[Chevyracincamaro]

this there anyone out there that knows how an ECU is programmed. im not asking about like hypertech power programmer stuff. what language is used? what kindof data structures are implemented? does an ECU use high level programming or is it base level stuff, or machine code or something? im aggrivated that i have to buy a device to reprogram my PCM when i am perfectly capable of doing it myself...

[ohiostate]

There are many different things that go into programming an ECU. The problem is that they (the automobile companies) do not want normal people, like you and me to be able to mess with what is going on with the engine for liability and warranty reasons. With the LS1, the PCM (Powertrain Control Module) is very easily changed and reprogrammed to what you want it to be, if you know where all the locations are in the stock code. The trick is figuring out where these locations are because they are scrambled. The people at LS1edit and HPTuner know these locations already and make software that can change these parameters. I am sorry if this is information that you already knew, but if anyone else knows the actual locations of different things in the actual codes or how to figure that out, I would be very interested as well. I am really interested in making this a career, and any experience I can get with programming vehicle computers would be invaluable. Any incite please!

[SaabJohan]

First, it's the maps that you're supposed to modify, keep away from the ECU software as this is made by the car manufacturer and should be as it is.

The maps are in hexadecimal code so in theory you just need a hex editor to modify it. In reality that's not the case as you don't know what is what.
So to modify the code you will need to develope a tool that can translate this code into maps for fuel, ignition and so on. The car manufacturers use a tool like that, and some tuners got their hands on them and use them (many also steal or buy complete softwares for the ECU, some develope their own tools), car manufacturers also have a development ECU.

So when you have found out what is what, then you must find out which values you can change, and what to change them to. Usually the modifications done is extremly small, and you will also need a dyno to do this.

To develope a tool for one of the latest and most advanced systems on the market, plus modifying the values in it is work that will take months if not years for one person.

[SaabJohan]

Here you can find some info about a few older systems, you can also download the code from a few engines.

http://www.ludd.luth.se/users/rotax/