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www.diy-efi.org is a great source of information on GM vehicles. The guys there have reverse engineered many GM ecms and distribute their work for free.

Right now I'm working on a GPL'd bin editor, and once that's done I'll be working on a PROM burner that works in Linux.

Oh, I should add a link to www.moates.net as well, since he makes lots of cool stuff like PROM emulators and USB programmers. Craig's gonna kill me...

For more information see DIY-EFI and related mailing lists. The reason not to use a PC is that PCs are not designed to handle the abusive environment inside a car. It would be best to build a simple computer with the appropriate circuitry to handle automotive signals (mostly a lot of 5V stuff, with some notable exceptions like your typical crank angle sensors and O2 sensors) out of something simple like a uCDIMM.

I have it on very good authority that EFI gets at LEAST 15 miles more to the gallon than your puny little Civic.

SEE????

* clueless mods: please look up "EFI" within the context of the article. thanks.

The computer which controls the engine of a car is not rocket science. There a projects in existence to build Do-It-Yourself Electronic Fuel Injection computers. In addition, a standard piece of auto electrician kit is a small box which provides a set of fixed strobes to drive the fuel injectors, allowing a car with broken (or disabled) EFI to drive away (with potentially reduced performance). The circuit is not much more than a 555 timer driving a few flip-flops. Ultimately, any criminal can easily find a substitute for the 'standard' EFI controller in a car, thus bypassing any disabling features.

This leaves honest people as the only ones susceptible to a 'remote control for cars'. Consequently the only real use for such a feature would be to simplify life for car-jackers.

Go to this link and see what people have done already. Lotsa hacking going on there...the entire GM Engine Computer has been reverse engineered. I drive a GMC Typhoon...and there are several guys on the "syty list" that have really taken apart the code, and made it possible to change all sorts of things. There is even a programmable box you can use to flip through various programs of timing and fuel.

Depending on the vehicle, you may be able to do some crazy things with it. As has already been said, after '96 all cars in the US have to speak OBDII (used for emissions testing...at least in some states). There are different physical interfaces, but for OBDII cars not all that many.

IMHO, the real fun is with OBDI cars. My weapons of choice are a '94 Firebird Formula (5.7L LT1) and the following interfaces/software:

- SerialALDL interface from AKMCables

- Datamaster PCM Diagnostic software from TTS Power Systems. This is some of the best software ever, and they have versions for LOTS of OBDI and OBDII vehicles. I get realtime powertrain info from the PCM as well as lots of great ways to interpret/display it.

- LT1Edit PCM re-flashing software from Carputing LLC. I can tweak any tunable value in my PCM and re-flash it in about 5 minutes through the under-dash ALDL connector. They also have LS1_Edit for the LS1 crowd (newer Firebirds/Camaros, and they support V8 trucks, etc now too).

Other goodies available are:

- Mike Chaney's Home Dyno/Road Dyno. Is a sweet little software/hardware package to measure engine performence generall within +/- 3% of a real inertial dyno. And cheap too!

- Andy Whittaker's FreeScan for ALDL OBDI vehicles is a free scan tool for realtime engine data. Pretty nice.

- The DIY_EFI folks at diy-efi.org run a GREAT mailing list for those interested in do-it-yourself fuel injection tuning.

- TunerCat is a suite of tools for dumping/modifying/flashing (or burning) PCM programs for various GM ECMs.

- The old standby Diacom from Rinda Technologies is DOS-based ECM scan tool software. It's OK, but they really should update it and lower prices to compete.

- For the Mustang crowd there is the Tweecer for tuning EEC-based Ford 5.0L engines. I don't have a Mustang, but this appears to be the sweetest little package for tuning them.

I could keep going on for days here, but real work calls... :)

-d

Actually, this is already happening. Check out this site for information.

Ahh, if you thought the older computer carb stuff was cool, you should really look into what's being done with modern aftermarket EMS'es and EFI. For example, the MoTEC can do everything from traction control to programmable boost control by gear, load level, and speed.

It's possible to do the sort of stuff you're talking about with a modern injection system and something like the S-AFC or eManage piggyback computers.

If you were doing car/computer geeking back that far, you might well have *lots* of fun with what it's possible to do now. Drop by the DIY-EFI site and check out the work in progress.

Well, *all* vehicles sold in the US after the 1996 model year are federally mandated to have OBDII. It's true that few of the interfaces have tunable parameters, but the interface is there, and can be read from. Yes, manufacturer-proprietary interfaces for setting parameters are causing problems in the field of aftermarket OBDII software, but it certainly exists in many forms.

Plus, there are certainly other EMS's available for less than the $3000 range, such as the Haltech, Microtech, and even the Megasquirt, which, while not unencumbered, has at least source and schematics available. It's just not to be used commercially without authorization. While I'd welcome a Free EMS, it's probably better to add your skillset to the DIY-EFI group, as they're already working on this.

DIY EFI is somewhat related, you will find tons of information on fuel-injection systems, with an emphasis on GM products. The mailing list archives go back about 5 years, with people posting from all different backgrounds, including Ford engineers.

I've got an '94 LT1 in my '86 Jaguar XJS. It runs 14sec 1/4mi at ~100mph. Crosses the finish line in 2nd gear (running 2.88 gears) and can get over 30mpg with long hwy driving. Car computer hacked with LT1Edit by Carputing.

Megasquirt is a stand alone fuel injection controller. The Megasquirt is a diy project that could be adapted to many engine applications.
Another good reference is diy-efi.org.

Both of these sites offer projects that would be smaller scaled and could be relativly cheap. Of course after mastering a diy efi you may be inclined to open up your daily driver!

You might want to check out the mailing lists at www.diy-efi.org. I don't think there are any linux efforts going on there at the moment, but they do have a lot of knowlege in reverse engineering OEM systems and building them from scratch.