|EFI system ECU
|| The basic function of the ECU is to control the pulse width of the injector. In engine management systems, the ECU controls additional functions, such as idle speed, ignition timing, and fuel pump operation.
|Electronic control unit settings
||The ECU corrects ignition timing to achieve the optimum setting for each operating condition.
|Engine speed limiting
||An ECU can control engine speed limiting, the fuel pump, exhaust gas recirculation, idle speed control, a variable intake manifold, and the evaporative emission container.
|Malfunction indicator lamp
||A check engine lamp or a data scanner can be used to indicate problems in the engine management system. A code indicates where the fault may be.