Dual Thermo Valve (California Models)

Thermo valve is used to sense engine coolant temperature and prevent EGR operation when below preset values. When engine warms up, thermo valve opens to allow vacuum passage to dual EGR valve, which then determines EGR flow. At 95°F (35°C), one thermo valve opens to allow some EGR flow. Above 131 °F (55°C), second thermo valve opens and more EGR flow is accomplished.

Fig 1: Sectional View of EGR System (Federal Models)

Courtesy of CHRYSLER GROUP, LLC

Fig 2: Sectional View of EGR System (California Models)

Courtesy of CHRYSLER GROUP, LLC