Engine Control System; General - Toyota 2006 PRIUS Manual

12
1NZ-FXE ENGINE

ENGINE CONTROL SYSTEM

1. General

The engine control system of the 1NZ-FXE engine on the '06 models has following systems.
System
SFI
(Sequential Multiport Fuel
Injection)
ESA
(Electronic Spark Advance)
ETCS-i
(Electronic Throttle Control
System-intelligent)
VVT-i VVT i
(Variable Valve
Timing-intelligent)
Coolant Heat Storage
System
Air-fuel Ratio Sensor,
Oxygen Sensor Heater
Control
Fuel Pump Control
Cooling Fan Control
NEW FEATURES - 1NZ-FXE ENGINE
Outline
An L-type SFI system directly detects the intake air
mass with a hot wire type mass air flow meter.
Ignition timing is determined by the ECM based on
signals from various sensors. The ECM corrects
ignition timing in response to engine knocking.
The ECM optimally controls the throttle valve opening
in accordance with the engine conditions and the
ETCS-i control request received from the HV ECU.
Controls the intake camshaft to an optimal valve
timing in accordance with the engine conditions and
the control request received from the HV ECU.
The maximum retard closing timing of the intake valve
has been changed from 115_ to 105_ ABDC (After
Bottom-Dead-Center). As a result, the cold-starting
performance of the engine has been improved.
The ECM actuates an electric water pump in the
coolant heat storage system to recover the coolant
heated by the engine, store the hot coolant in the
coolant heat storage tank, and supply it to the engine
before starting a cold engine. This optimizes the
combustion performance of the engine during
cold-starting and reduces HC exhaust emissions.
The temperature of the air fuel ratio sensor or oxygen
sensor is maintained at an appropriate level to increase
accuracy of detection of the oxygen concentration in
the exhaust gas.
Fuel pump operation is controlled by signal from
the ECM.
A fuel cut control is used to stop the fuel pump when
the airbag is deployed during front or side collision.
The ECM steplessly controls the speed of the fans in
accordance with the engine coolant temperature,
vehicle speed, engine speed, and air conditioning
operating conditions. As a result, the cooling
performance has been improved.
'06 '05
Models Models
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