
EC-16 EMISSION CONTROL SYSTEMS — Exhaust Gas Recirculation (EGR) System (7M-GTE)
EXHAUST GAS RECIRCULATION (EGR) SYSTEM (7M-GTE)
(1)
EGR Vacuum
Modulator
EGR Port
EGR Valve
VSV
E···E
ECU
EGR
VSV Vacuum
Modulator
EGR Cooler EGR
Valve
EC3330 EG2283
(2)
EGR Port
VSV
E···E
ECU
EGR
Vacuum
Modulator
EGR Cooler EGR
Valve
EG2380
To reduce NOx emissions, part of the exhaust gases are recirculated through the EGR valve to the intake manifold to lower
the maximum combustion temperature.
Coolant VSV Throttle Valve Pressure in the EGR EGR Vacuum EGR Exhaust Gas
Temp. Opening Angle Valve Pressure Chamber Modulator Valve
Below 57°C CLOSED
(135°F) (E—G) — — CLOSED Not
recirculated
Above 63°C OPEN Positioned below
(145°F) (E—G) EGR port (1) — CLOSED Not
recirculated
Positioned above
EGR port (2) * CLOSES passage OPEN Recirculated
to atmosphere (Increase)
* When the throttle valve is positioned above the EGR port, the EGR vacuum modulator will close the atmosphere
passage and open the EGR valve to increase the EGR gas, even if the exhaust pressure is insufficiently low.