Hack Your Car

gurps_npc writes "The New York Times has this story about hacking your car's chip. You can get significant horse power and torque boosts (+18 horsepower and +70 foot pounds of torque in the given example), as well as improve (or decrease) fuel efficency. The car companies do not like (surprise surprise) people personalizing their vehicle's programming and warn of burning out your engine with bad code, and voiding your warranty."

Comments

This is no new thing

[CptChipJew]

People have been doing this ever since computer controlled fuel injection has been in style.

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

But if you think you're going to get another 70ft/lbs of torque in a Honda Civic by just doing that, think again.

As well, changing these values can be dangerous. I have a friend who quite messed up his Buick Riviera (he added fuel injection) by messing with the values. There was a huge table of values to fill out, and each had to be precicely tuned to achieve the right mix of performance and mileage. This is no easy task.

Re:This is no new thing

[BiggerIsBetter]

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.

Re:i can understand

[digitalhermit]

Firearms.
There are lots of self-loaders out there who think that adding more powder makes them shoot better. Or they modify their weapons because they read somewhere on the Internet that it would shave off a microsecond or two from the firing rate or lessen the trigger pull. Funny thing is that the people who have used the most bizarre rifles tend to shoot the worst.

Airplanes you say?
I live about 100 yards from a small airfield in South Florida. I was driving to work one morning and noticed a bunch of fire trucks and police a few doors away. Heard on the news later that day that an experimental plane had crashed into a house. I've seen a couple of these accidents so far (well, not the actual crash, but the after effects).

Home wiring...
I've visited lots of friends' houses that have really bad wiring jobs. I've seen lots of outlets that would fail inspection. At my last house the previous occupants had been running a small business from their converted garage. They had installed extra outlets to run the electrical equipment (heater, various electrical motors, etc..). Everything was connected to an extension cord with a bunch of daisy-chained power strips *behind the wall*.

Re:I dont think I would hack my car

[drinkypoo]

The thing about cars is that they are very analog devices. Fail to tighten a nut, and you will probably be able to get a feel for what happened if it's life threatening. Of course it depends on the nut, but in most cases something really major that you have forgotten will fail before you even get out of the driveway. This is not always true of course, but it frequently is. The real reason not to work on your car is that mistakes can be insanely expensive, and there's no restoring from backup. Alter your timing too much doing an engine rebuild, for example, and your valves might crash into your pistons and destroy your engine, or at least the pistons and the head. Almost all engines are "interference" engines like this, where moving parts' paths intersect, just not at the same time.

Most car stuff is pretty simple because there's a right way and a wrong way to do it. You can also trivially check the connections you've made to see if they are good before you crawl out of the spot you're in. Some things have to be tightened/loosened in stages and in a specific order, so provided you're following the proper instructions for the job, if you do it at all, and you do it properly, you can't leave something out.

Now let's say you're upgrading your brakes. In order to do this you're going to have to change (at least some of) your fluid, because it's going to have to come out of the system, because you're going to have to bleed it. So you change your calipers (one at a time so all the fluid doesn't fall out of the system immediately, which is inconveniently messy) and you install everything. Before you put a wheel back on, you check your connections; it's an obvious thing to do. Two bolts typically hold the caliper on, and there's one fitting where the brake line connects. (Drum brakes are much more complicated, I'm talking disc here.) But before you even put the wheels back on you're going to be bleeding the system, and any leaks will be apparent at this time because you're going to have to visit each wheel to accomplish this. In fact typically brake bleeding involves two people; one at the wheel to open and close the bleeder valve, and another in the car pumping the brake pedal appropriately. (There are tools which make this easier, the best of them is the speed bleeder. Most of the pumps and stuff don't work.) So just by the nature of the job you're going to see if there's something wrong. Most automotive work is like this.

Hacking your ECU usually primarily involves altering rev limits, and a "fuel map" which is a two dimensional matrix of throttle position to RPMs. This is where you can get into trouble, because you can make the mixture too lean which will cause pre-detonation or "knock" which can damage your engine (pistons, valves, rods, crank can all be damaged by early detonation.) But today's fuel injected cars are often fairly idiot proof in that unless you completely change their code and don't just change some values in a lookup table, they have assorted failsafes which they use to alter the behavior of the car even after the fuel map is consulted. For instance you can stop detonation by retarding the timing (beyond a certain point) and if your engine has a knock sensor (most things made in the nineties and later do) the car will automatically retard timing when it detects knock. It will also make the mixture leaner or richer based on feedback from the O2 sensor for the purposes of emissions, but this is also good for power, because the more efficient you run, the more power you will get for a given amount of fuel delivery. There is certainly more to it than this, but it's a broad overview. Altering rev limits is pretty risky too, because if your engine is not balanced well enough to make more RPMs than the limiter, you will destroy parts of your engine, like bearings, by revving it up that high. It's definitely not a good idea for older motors which haven't had a rebuild in some time.

Cars are moderately complicated, especially these days, but anyone smart enough to work on computers successfully is smart enough to work on cars, too. It mostly requires the inclination.