A little over two decades ago ECUs or electronic control units were introduced to passenger vehicles. ECUs drastically changed how modern cars operate, making them more efficient in the production of power, pollution control and fuel consumption. A car’s ECU manages multiple aspects of the engine’s combustion process as well as several other functions. In fact the tasks a car’s ECU performs have steadily increased over time.
Tuning your car’s ECU is a relatively quick and inexpensive way to unlock additional power. Car manufacturers must meet an array of demands for fuel economy, pollution and longevity that leaves room for improvement in an ECU’s software or “map.” When you tune a car’s ECU, you either alter the map for greater performance or you completely erase the old map and load a new one. Remapping or flashing a car’s ECU is a complex task that must be performed by a licensed and highly qualified car technician. In fact, car manufacturers often use ECU tuning to make different trim levels of the same car produce more power. Altering a vehicle’s map might void the manufacturer’s warranty, so check with the car’s manufacturer before proceeding.
You can tune your car’s ECU using one of two methods. The first method is the quickest, cheapest and easiest to perform. You buy a new computer chip for your car’s ECU, which comes with a new map. All you have to do is remove the old ECU chip and install the new one to load the new performance map. The new ECU chip should be programmed by a qualified car technician. Some aftermarket ECU chips that are not properly programmed can actually do serious damage to a car’s engine, so exercise caution and investigate how a chip is programmed before installing it in your car.
The second method of ECU tuning must be performed by a qualified car technician at a shop. The technician literally plugs a computer into the car’s ECU and reprograms a portion or the entire map. Depending on the make and model of a car, the wiring harness that connects the ECU with the car’s various sensors must be replaced to complete the tuning process. The entire process can take several days to successfully complete, especially since most shops will subject the car to a series of tests to ensure it is operating correctly.
The only accurate way to measure the performance benefits of an ECU tune is to hook the car up to a dyno. A car dynamometer measures the horsepower and torque output produced by the engine, graphically displaying the level of output from an idle all the way to the engine’s redline in each gear. Most tuning shops will subject a car to a dyno test before finalizing the ECU tune.
Some car owners worry about what parts they should install on their car before tuning the ECU. In general a car’s ECU will adjust its operation as you install new performance parts, making it a good early modification to perform. Still, there are a few modifications that are best done before the ECU is tuned. Adding forced induction in the form of a turbocharger or supercharger is best done first, as are upgraded driveline and engine parts like high-performance valves, pulleys, pistons or crankshafts.