Toyota 4-Runner 1985 Repair Manual page 171

FI-2
EFI SYSTEM - System Description
SYSTEM DESCRIPTION
Ignition
Switch
Air Thermo
Sensor
Brake Switch
Terminal "VF" l}ooII~"'"
The EFI used on Toyotas has three basic systems.
FUEL SYSTEM
An electric fuel pump supplies sufficient fuel, under
a constant pressure, to the EFI injectors.
These injectors inject a metered quantity of fuel into
the intake manifold in a.ccordance with signals from
the ECU. Each injector injects, at the same time,
one half of the fuel required for ideal combustion
with each engine revolution.
AIR INDUCTION SYSTEM
The air induction system provides sufficient air for
engine operation.
Fuel Tank
VSV (for 4WD)
Ignition Coil
WI
igniter
Throttle Position
Sensor
Distributer
FI0590
ELECTRONIC CONTROL SYSTEM
The 22R-EC engine is equipped with a Toyota
Computer Control System (TCCS) which centrally
controls the EFI, ESA, Diagnosis systems, etc.
by means of an Electronic Control Unit (ECU -
formerly E F I computer) employing a microcom-
puter.