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I've got a real-time OS (QNX) running my Suburban but while I'd like to think that there's a separate chip running the engine management, I confess to being ignorant. The Megasqurt community would certainly know more...

While I agree it is not feasible to home-brew an internal combustion ECM for a modern automobile,

You guys are all sitting around arguing if it can be done, when it has already been done. Megasquirt is a homebrewed ECU which can be twiddled in build for different injector drivers etc. You can use it as a replacement PCM for tuning or you can use it for adding EFI to a carbureted vehicle.

You guys think that ECMs are rocket surgery or something, but they frankly are not. Yes, there's a lot of noise underhood, but the ECM is located in a metal box. Yes, there's a lot of vibration in a car, but the metal box of the ECM is normally shock-mounted. And you think it's hard to do better than the real guys, but they screw it up too, and they don't try particularly hard.

Remember, companies were throwing together working ECMs back in the eighties out of discrete components and one dinky microcontroller. Hitachi used a 3 MHz 6800-series chip in the computers that ran the Impreza, 240SX and some of its other contemporaries.

you can replace the proprietary engine control computer with one of these The source is open. Controls fuel injectors, Ingition etc. Maybe he's already using one on his car if he even drives at all. Only know a few autistic genius types that even drive a car.

You do not have to use the ECU for that particular car. There are projects for aftermarket ECUs. http://www.megasquirt.info/

I know you weren't implying that you have something right this second you would like to replace but Megasquirt is pretty much exactly what everyone is looking for. It's quite a nifty project, and seems to be gaining a decent following.

Just replaced the ECM (recall) on my wife's '05 Corolla. Also, please note the incredibly cool MegaSquirt (open source engine management).

Why worry about your car while you carry a cellphone? California designed OBD2 car controllers to have antennas and report VIN, speed, overdue maintenance & more. Feds clipped the antenna & mandated OBD2 in 50 states in 1996(?). Tinfoil may work but try these: http://www.megasquirt.info/ http://www.diyefi.org/ http://www.msefi.com/index.php You can also buy commercial replacements for you drivetrain controller. Before you talk about it, remove your cellphone battery.

I'm surprised no one has mentioned MegaSquirt yet.

Very functional, do-it-yourself fuel injection system that can be used on nearly any motor. Build your own go-kart, anyone?

http://www.megasquirt.info/

that will get you started on the software end.

hardware (engine design, etc)

you'll have to dig around or check this out:

http://www.theoscarproject.org/

an opensource car project.

You already can.

Don't underestimate the car company's efforts to limit us! Of course, limiting a person's understanding of a machine in which even the smallest parts can been seen and manipulated by a person without the need of a SEM is a little bit harder, and government mandates make sure that there is at least a standard method to getting diagnostic info from the engine computer, car companies such as BMW sign the software in ROM, and design the CPU/microcontroller to not run unsigned code or fuel mappings. I don't know how it works, but you would need something that had the same effect as an xbox modchip.

Other manufacturers don't have the same protection, and even if they do, there is an open source design available, called MegaSquirt. (And that's the second time I got to throw that in there this week! No, I don't use it. Ford's EEC-V is pretty well understood and works fine :P

Pfft. Who needs proprietary EEC operating systems? Or operating environments, for that matter! Next, I'll open source my cat!

You don't need to wait for the auto manufacturers -- simply replace the stock ECU with a MegaSquirt ECU, for which source code and schematics are available. You can buy a kit with all of the parts and the pre-programmed EEPROM, or you can buy a pre-assembled and pre-programmed from here -- even plug-and-play wiring harnesses are available.

You, my friend, need to build yourself a MegaSquirt. You can build the whole thing by yourself for about $200, and the code is GPL. You can interface with the box using a serial cable, and there's a version of the code that lets you control both fuel and spark advance, as well as things like turbo wastegates and even nitrous if you want to go that far. Take a look; I learned things about cars I never knew just by building and installing one of these.

By "special tools" I think you mean "enough knowledge/confidence to not fear wiring" (and the oil change reset tool, maybe). :) The same tools I use to rebuild the 350 in my '71 Chevelle are useful to rebuild the engine in my '95 LT1 Caprice and my '04 Grand Marquis - and I'm pretty sure there were some metric wrenches required on your '78 Malibu. With new cars, though, I also have a computer that can tell me roughly what's wrong, which is pretty handy. The '95, actually, I bought specifically because of the computer. It's *sooo* much easier to get the fuel mixture right with fuel injection than with a carburetor (my '71 Chevelle and '75 El Camino are still carb'd onl (with an electronic overdrive transmission too, gasp!), EFI will be pretty much mandatory. You just can't [reasonably] make a carb alter its mixture based on the ethanol content in the tank at any given time. Megasquirt can, though.

BTW, the compression tester, vacuum gauge, dwell meter, oil pump primer, timing gear puller, and piston ring compressor from rebuilding the '78 aren't useful for much of anything outside of auto repair... Nor can you transfer the skill required to install that stupid short hose connecting the water pump to the intake manifold on a Chevy big block. ;)

I think someone has fuel injection covered already. Check out this experimental do-it-yourself programmable electronic fuel injection controller. And it seems the nature of that fuel injection project would work just fine for an open source car. Even supports wideband O2 and a decent range of tuning, so you could hotrod your OScar if this was used. Throw in a Megaspark, put it on a common board and you've got a workable ECU.

Any vehicle on the road today can have its ECU replaced by a standalone engine management system. Once it's installed, you can then genuinely hack your car's engine as well. If you don't like expensive propretiary systems, there's even "open source" alternatives like MegaSquirt

Here ya go, some do-it-yourself guys made this site. MegaSquirt. Looks pretty fun.

If you peruse eBay, you'll see people selling replacement chips for around $400 that are supposed to add this many horsepower.

And unless you buy a matched kit with cam, inlet, exhaust, etc, you're just gambling that it will work better than your existing setup. If you're paying $400 for a chip, you'd be better off buying (or building) a programmable computer instead. Then spend some dyno time and get it set up right.