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.