Engine Control Unit (ECU) Magic.
The engine control unit (ECU) or engine management system (EMS) is certainly a revolutionary innovation. It was only an idea in someone’s mind’s eye back in the 1970s and 1980s. Indeed, electronic controls for automotive applications were still in their infancy then. Cars’ engines were mechanically controlled. Carburetors were crude and inefficient mechanical devices; its main purpose: to atomise the fuel. It was these components that were at the order of the day. They were temperamental things, stuttering when cold, heaving when cornering, and sometimes just doing a terrible job. The mechanical distributor was responsible for spark timing and was in itself prone to wear.
Can you recall that little rotor spinning inside a housing in order to distribute spark to the spark plugs? A vacuum-advance mechanism would modify distributor timing to allow for differing engine loads. Old-fashioned CFI (continuous fuel injection) systems continuously sprayed fuel, whether the inlet valve was open or not. Regulating this process, was a simple fuel pressure regulator.
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With progress comes change
It is true, with progress comes change. With the engine control unit, a lot of change came with it. Many of the mechanical devices in your car have now been replaced with electronic components. The remaining ones did not dodge progression, they simply became electronically controlled. The distributor is gone. The central ECU determines the optimal spark timing and adapts it according to inputs from many sensors. The injectors are sequential and only open when the need requires it. The ECU even controls the amount of fuel injected.
Engineers determine the optimal spark and fuelling regime for every rev point and throttle opening. They then programme these values into tables they call maps. As a result, a great many different maps are therefore stored in an ECU. Whenever there is a need for it, the ECU calls up these values and apply them. These maps control spark timing and fuelling, rev limiter and, in cars with turbochargers, the boost pressure.
A safer way to optimise.
In the olden days, one had to physically change mechanical components to change these parameters. Think about replacing the spring of the turbo wastegate with a stiffer one to obtain more boost pressure. Nowadays, we simply modify the programming of the engine control unit. This makes it much easier to tune cars. Many people believe that you should leave your car’s ECU settings alone. There are also many who wonder whether the ECU is perfectly tuned when it leaves the factory? If you want to leave your ECU as is, then that is your choice. With regards to the tuning of the ECU, no, it is not perfectly tuned.
You see, it is expensive and time-consuming to develop a detailed map for every type of engine. What manufacturers do is to write one set of maps. This set then caters for all engines of a certain type, in all climates, altitudes, driving styles, and fuel types. Therefore, the standard “one map fits all” they develop, leaves ample room for improvement. This is especially true when you apply it to a specific engine under known conditions. In some cases, the standard programming can seriously restrict an engine.
Don’t be afraid to optimise your car’s ECU. A Unichip can make a measurable difference to your engine’s economy and power output, by optimising the existing ECU programming in a non-invasive way. It may be a surprise to you, but with the Unichip, there is almost always some room for vehicle improvement. Practice responsible car care. Become part of the Unichip family and buy your Unichip today. Click here to contact us.