Toyota 2VZ-FE Manual page 114

FI–7
EFI SYSTEM – Operation (System Operation)
ELECTRONIC CONTROL SYSTEM
The control system consists of sensors which detect various engine conditions, and a ECU which determines
the injection volume (timing) based on the signals from the sensors.
The various sensors detect the intake air volume, engine rpm, oxygen density in the exhaust gas, coolant
temperature, intake air temperature and atmospheric pressure etc. and convert the information into an electrical
signal which is sent to the ECU. Based on these signals, the ECU calculates the optimum ignition timing for the
current conditions and operates the injectors.
The ECU not only controls the fuel injection timing, but also the self diagnostic function which records the
occurrence of a malfunction, ignition timing control, idle rpm control, EGR control, fuel pressure control and fuel
pump control.