Engine Management

Put simply, Engine Control Units (ECUs) are designed to electronically control fuel  injected internal combustion engines.

 

In its most basic form an  ECU monitors the engine through sensors and uses this information to  determine the quantity of fuel to inject and the timing of the ignition  depending on engine speed (RPM)  and engine load conditions. Typically, an ECU will use throttle  position, manifold absolute pressure (MAP) or mass air flow (MAF), or a combination of these to calculate the load  conditions.

 

Programmable ECUs

All calibration and  tuning parameters in a factory ECU are fixed by the manufacturer to suit  the engine in its standard form and it is often impossible to adjust  this for engine modifications.

However, if the factory ECU is  replaced by a programmable aftermarket system, adjustments can be made.  An engine tuner can connect the ECU to a PC to tune the engine for  optimum performance at each load and speed condition. This requires  dedicated tuning software and the sophistication of this software is one  of the key differentiating factors from one brand to another.

 

Modern Functionality  

These days,  aftermarket ECUs not only control injection and ignition timing, but  also manage more complex functions like boost control, idle speed  control, intercooler spray bars and traction control. Many ECUs provide  extra auxiliary outputs that can be used to activate devices such as  pumps, fans and even servo motors.

Recent  engine development has led to electronic innovations like continuously  variable camshaft timing and drive by wire throttle systems. This has  created a need for more sensor inputs and auxiliary outputs and a higher  processing speed in the ECU.

 

Data Logging

 

ECUs with on board data  logging provide several advantages for  the tuning of high performance  engines, allowing users to record and then analyse various engine  parameters. The detailed information can be used for fine-tuning the  engine and targeting small refinements that can deliver significant  performance gains. Logging is also an invaluable tool in helping to  detect early signs of engine health problems.