Ok, me and my brother are going to try reprogramming his ECU. Yet we are a little fuzzy on how to connect to it and what software to use? So if you can help with these issues that would help a lot. Also is it possible to do it with a pda (Visor deluxe). A truely wise person doesn't denie his flaws but embraces them.

If you are talking about the Electronic Control Unit in a motor vehicle I would think long and hard. First thing you will need is the documentation from the manufacture. Thats is likely to be hard to come by if not impossible. Without you are playing with fire. The ECU is like the BIOS in a computer, get it wrong and nothing works. Like the BIOS in the computer, it will different for each manufacture. Just on other thing to consider. The ECU contains code that is used by the emission control systems. Modifying that to increase performance could put you on the wrong side of the law. Stuart

Frankly, this is one of the most complicated embedded projects to undertake. You sound a little crazy to consider reprogramming when you're not sure about how to hook the pieces up. Anyway... The ECU is an embedded device. Most ECU's are EEPROMS sitting a PCB somewhere within reach of the driver's seat (perhaps under it). The brains can be something like a Motorola microcontroller (~$25), though makers have many options. Basic electrical knowledge is required. Tinkering is done by either removing the entire PCB unit or just the actual data module (and then hooking it up to a test board). Either way, you can usually connect via a serial port to your computer. The professional (and best) way to do it is buy a new board altogether. From there, you need a development environment with the proper assembler. Most IDEs come with or connect to a program that will flash the memory and add your code. You can flash thousands of times. I have no idea what IDE you would want or need. For programming, you are going to need to know the particular subsystem (which usually controls another nest of subsystems) and associated sensors. Also, the ECU works with many different components almost directly, so you need to know these interfaces. There are limits to your vehicle and its components you must know. You will almost certainly work in assembly (watch number units). Reading sensor output is essential, so at the very least hook up an LED display. You could hook up a PDA, but that will likely require a slew of additional knowledge.

Thanks, IF i do it ill share if i destroyed the car or not :D. A truely wise person doesn't denie his flaws but embraces them.