An ECU stands for engine control unit, or also known as PCM (powertrain control module.) In layman's terms, this little do-dad is a small computer that communicates with the engine and determines almost everything which makes your engine something to boast about. Everything meaning literally everything, a short list that the ECU controls would be; horsepower, torque, how much carbon dioxide is being exhausted, how mush fuel to pump, idle speed, ignition timing, and even the time in which all the valves open up. This can be considered the brain of the car. At least for modern cars, it is almost impossible to build an emission-passing car without a computer a.k.a. ECU.
So why should it be upgraded? Just like any other normal computer, they love to updated and upgraded. Just as a normal computer the more it is upgraded the better it will run. The more RAM the faster and more responsive it is, the more hard drive space the less frequently you have to delete something. It goes the same with fuel, the better control the ECU has over the air to fuel ratio the less frequently you have to fill up. Also just like your laptop being faster, your car becomes faster and has a more responsive throttle thanks to the extra horsepower and torque.
Some ECUs even have programs that they can run. Programs such as; 91, 93, and 100 octane mode, this lets your engine work as efficient as possible with which octane gasoline is available. Valet mode, which limits the engines power. Anti theft mode, which lets you set a passcode before starting the car, making it impossible to steal the car, at least by starting it.
How much does an ECU upgrade cost? For cars that are not in the hundreds of thousands of dollars, an upgrade can range from 300-800 dollars and only takes about 10-30 minutes to do. To get it done the best way is to take it into a shop that specializes in your make of car, do not bother going back to the dealer go just go to a tuning shop. Another way is to go online print a form and physically send your ECU into them, but then you’ll be out of a car for a while since your car will not have a brain. One other way is to do it yourself.
This is very simple to do, if you want to do this on your own. All you need is a MPPS cable, a laptop and the software file. Turn off the cars engine, Plug in the MPPS cable into your car’s cable port, which is usually under the steering wheel and obviously into your computer. Then upload the file using whichever computer software is for your car. Then feel free to make a list of all the other sweet mods you need to do to your baby. 30 minutes later, have fun with your smarter and better car.
Obviously, take your car to your own tuning company here is a short list of links to some tuning companies.
Audi, Porsche, Seat, Skoda, and Volkswagen
Diesel Ford, Dodge, GM
http://www.ralliart.com/index.html (Division is no longer in retail for tuning parts)
BMW, Mazda, Mini, Mitsubishi, Nissan, Scion, Subaru
Honda, Mitsubishi, Toyota, Nissan, Subaru, Mazda, Suzuki, Ford
Honda, Nissan, Mitsubishi, Scion