EGR Valve: Description and Operation

- Increases or decreases the flow of exhaust gas recirculation
- As vacuum applied to the EGR valve diaphragm overcomes the spring force, the valve begins to open
- As the vacuum signal weakens at 5.4 kPa (1.5 in-Hg) or less, the spring force closes the valve.
- Fully open at about 15 kPa (4.5 in-Hg).