Efi (Electronic Fuel Injection ); General - Toyota COMPUTER-CONTROLLED SYSTEM Training Manual

EFI - Genera l
EFI
(ELECTRONIC
FUEL INJECTION )
GENERAL
The Engine ECU calculates the basic fuel signal . It bases its calculations on a program
injection duration in accordance with two stored in its memo
ry
.
signals : 1) the intake manifold pressure signal (in The Engine ECU also determines the optimum
D-type EFI) from the manifold pressure sensor, fuel injection duration for each engine condition
or the intake air volume signal (in L-type EFI) based on signals from various other sensors .
from the air flow meter, and 2) the engine spee d
Air cleaner
Pressure regulato r
Manifold pressure senso r
Engine EC U
Engine
speed
Sensors
Fuel filter
Fuel tank
(with built-in
fuel pump )
OHP 4 2
BASIC CONSTRUCTION OF D-TYPE EFI SYSTE M
Engine EC U
Engine
speed
Sensors
BASIC CONSTRUCTION OF L-TYPE EFI SYSTEM
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